diff --git a/amiga/gui.c b/amiga/gui.c
index 8d6d19ee4..9bf049a15 100644
--- a/amiga/gui.c
+++ b/amiga/gui.c
@@ -2132,12 +2132,11 @@ void ami_handle_msg(void)
 									GetClickTabNodeAttrs(tab,
 										TNA_UserData, &bw,
 										TAG_DONE);
-									bw->reformat_pending = true;
 								} while(tab=ntab);
 							}
 
 							ami_schedule(0, ami_gui_refresh_favicon, gwin);
-							gwin->bw->reformat_pending = true;
+							browser_window_schedule_reformat(gwin->bw);
 							ami_schedule_redraw(gwin, true);
 						break;
 					}
@@ -2206,13 +2205,6 @@ void ami_handle_msg(void)
 //	ReplyMsg((struct Message *)message);
 		}
 
-		if(node->Type == AMINS_WINDOW)
-		{
-			/* Catch any reformats tagged by the core - only used by scale? */
-			if(gwin->bw->reformat_pending) {
-				ami_schedule_redraw(gwin, true);
-			}
-		}
 	} while(node = nnode);
 
 	if(ami_menu_window_close)
@@ -2956,7 +2948,6 @@ void ami_gui_hotlist_toolbar_add(struct gui_window_2 *gwin)
 				gwin->win, NULL, TRUE);
 		
 		if(gwin->bw) {
-			gwin->bw->reformat_pending = true;
 			ami_schedule_redraw(gwin, true);
 		}
 	}
@@ -2998,7 +2989,6 @@ void ami_gui_hotlist_toolbar_remove(struct gui_window_2 *gwin)
 	RethinkLayout((struct Gadget *)gwin->objects[GID_MAIN],
 			gwin->win, NULL, TRUE);
 
-	gwin->bw->reformat_pending = true;
 	ami_schedule_redraw(gwin, true);
 }
 
@@ -3111,7 +3101,6 @@ void ami_toggletabbar(struct gui_window_2 *gwin, bool show)
 			gwin->win, NULL, TRUE);
 
 	if(gwin->bw) {
-		gwin->bw->reformat_pending = true;
 		ami_schedule_redraw(gwin, true);
 	}
 }
@@ -4043,7 +4032,7 @@ static void ami_redraw_callback(void *p)
 {
 	struct gui_window_2 *gwin = (struct gui_window_2 *)p;
 
-	if(gwin->redraw_required || gwin->bw->reformat_pending) {
+	if(gwin->redraw_required) {
 		ami_do_redraw(gwin);
 	}
 
@@ -4072,7 +4061,6 @@ void ami_schedule_redraw(struct gui_window_2 *gwin, bool full_redraw)
 	if(full_redraw) gwin->redraw_required = true;
 	if(gwin->redraw_scheduled == true) return;
 
-	if(gwin->bw->reformat_pending) ms = nsoption_int(reformat_delay) * 10;
 	ami_schedule(ms, ami_redraw_callback, gwin);
 	gwin->redraw_scheduled = true;
 }
@@ -4303,6 +4291,21 @@ static void gui_window_update_box(struct gui_window *g, const struct rect *rect)
 	ami_schedule_redraw(g->shared, false);
 }
 
+/**
+ * callback from core to reformat a window.
+ */
+static void amiga_window_reformat(struct gui_window *gw)
+{
+	struct IBox *bbox;
+
+	if (gw != NULL) {
+		GetAttr(SPACE_AreaBox, (Object *)gw->shared->objects[GID_BROWSER], (ULONG *)&bbox);
+		browser_window_reformat(gw->shared->bw, false, bbox->Width, bbox->Height);
+
+		gw->shared->redraw_scroll = false;
+	}
+}
+
 static void ami_do_redraw(struct gui_window_2 *gwin)
 {
 	struct Rectangle rect;
@@ -4325,13 +4328,6 @@ static void ami_do_redraw(struct gui_window_2 *gwin)
 	xoffset=bbox->Left;
 	yoffset=bbox->Top;
 
-	if(gwin->bw->reformat_pending)
-	{
-		browser_window_reformat(gwin->bw, false, width, height);
-		gwin->bw->reformat_pending = false;
-		gwin->redraw_scroll = false;
-	}
-
 	if(gwin->redraw_scroll)
 	{
 		if((abs(vcurrent-oldv) > height) ||	(abs(hcurrent-oldh) > width))
@@ -5073,6 +5069,7 @@ static struct gui_window_table amiga_window_table = {
 	.set_scroll = gui_window_set_scroll,
 	.get_dimensions = gui_window_get_dimensions,
 	.update_extent = gui_window_update_extent,
+	.reformat = amiga_window_reformat,
 
 	.set_icon = gui_window_set_icon,
 	.set_title = gui_window_set_title,
diff --git a/atari/deskmenu.c b/atari/deskmenu.c
index 8de2e327f..53e24a4d4 100644
--- a/atari/deskmenu.c
+++ b/atari/deskmenu.c
@@ -394,7 +394,9 @@ static void __CDECL menu_inc_scale(short item, short title, void *data)
 	if(input_window == NULL)
 		return;
 
-    gui_window_set_scale(input_window, gui_window_get_scale(input_window)+0.25);
+	browser_window_set_scale(input_window->bw,
+		browser_window_get_scale(input_window->bw) + 0.25,
+		true);
 }
 
 
@@ -403,7 +405,9 @@ static void __CDECL menu_dec_scale(short item, short title, void *data)
 	if(input_window == NULL)
 		return;
 
-    gui_window_set_scale(input_window, gui_window_get_scale(input_window)-0.25);
+	browser_window_set_scale(input_window->bw,
+		browser_window_get_scale(input_window->bw) - 0.25,
+		true);
 }
 
 
diff --git a/atari/gui.c b/atari/gui.c
index 608d0d859..efa23efe4 100644
--- a/atari/gui.c
+++ b/atari/gui.c
@@ -201,7 +201,6 @@ gui_window_create(struct browser_window *bw,
             option_window_x, option_window_y,
             option_window_width, option_window_height
         };
-        gui_window_set_scale(gw, 1.0);
         gui_window_set_url(gw, "");
         gui_window_set_pointer(gw, BROWSER_POINTER_DEFAULT);
         gui_set_input_gui_window(gw);
@@ -343,21 +342,14 @@ void gui_window_set_status(struct gui_window *w, const char *text)
         window_set_stauts(w->root, (char*)text);
 }
 
-float gui_window_get_scale(struct gui_window *gw)
+static void atari_window_reformat(struct gui_window *gw)
 {
-    return(gw->scale);
-}
+    int width = 0, height = 0;
 
-void gui_window_set_scale(struct gui_window *gw, float scale)
-{
-    int width = 0, heigth = 0;
-
-	LOG(("scale: %f", scale));
-
-    gw->scale = MAX(scale, 0.25);
-
-	gui_window_get_dimensions(gw, &width, &heigth, true);
- 	browser_window_reformat(gw->browser->bw, false, width, heigth);
+    if (gw != NULL) {
+	gui_window_get_dimensions(gw, &width, &height, true);
+	browser_window_reformat(gw->browser->bw, false, width, height);
+    }
 }
 
 static void gui_window_redraw_window(struct gui_window *gw)
@@ -1017,6 +1009,7 @@ static struct gui_window_table atari_window_table = {
     .set_scroll = gui_window_set_scroll,
     .get_dimensions = gui_window_get_dimensions,
     .update_extent = gui_window_update_extent,
+    .reformat = atari_window_reformat,
 
     .set_title = gui_window_set_title,
     .set_url = gui_window_set_url,
diff --git a/atari/gui.h b/atari/gui.h
index 978c0d093..10736c5f8 100755
--- a/atari/gui.h
+++ b/atari/gui.h
@@ -149,7 +149,6 @@ struct gui_window {
     char * title;
     char * url;
 	struct bitmap * icon;
-	float scale;
 	struct s_caret caret;
 	struct s_search_form_session *search;
 	struct gui_window *next, *prev;
@@ -168,7 +167,5 @@ char *gui_window_get_title(struct gui_window *gw);
 void gui_window_set_status(struct gui_window *w, const char *text);
 void gui_window_set_pointer(struct gui_window *gw, gui_pointer_shape shape);
 void gui_window_destroy(struct gui_window *w);
-void gui_window_set_scale(struct gui_window *gw, float scale);
-float gui_window_get_scale(struct gui_window *gw);
 
 #endif
diff --git a/atari/rootwin.c b/atari/rootwin.c
index fde0bd3b5..7c2cdbcf1 100755
--- a/atari/rootwin.c
+++ b/atari/rootwin.c
@@ -834,7 +834,7 @@ static void window_redraw_content(ROOTWIN *rootwin, GRECT *content_area,
 
     plot_set_dimensions(content_area->g_x, content_area->g_y,
                         content_area->g_w, content_area->g_h);
-    oldscale = plot_set_scale(gui_window_get_scale(rootwin->active_gui_window));
+    oldscale = plot_set_scale(browser_window_get_scale(rootwin->active_gui_window->bw));
 
     /* first, we make the coords relative to the content area: */
     content_area_rel.g_x = clip->g_x - content_area->g_x;
diff --git a/beos/gui.cpp b/beos/gui.cpp
index eee56d8c6..cb7effead 100644
--- a/beos/gui.cpp
+++ b/beos/gui.cpp
@@ -719,7 +719,6 @@ static void gui_poll(bool active)
 	int max_fd;
 	struct timeval timeout;
 	unsigned int fd_count = 0;
-	bool block = true;
 	bigtime_t next_schedule = 0;
 
         /* get any active fetcher fd */
@@ -734,34 +733,23 @@ static void gui_poll(bool active)
 	// max of all the fds in the set, plus one for select()
 	max_fd = MAX(max_fd, sEventPipe[0]) + 1;
 
-	// If there are pending events elsewhere, we should not be blocking
-	if (!browser_reformat_pending) {
-		if (earliest_callback_timeout != B_INFINITE_TIMEOUT) {
-			next_schedule = earliest_callback_timeout - system_time();
-			block = false;
-		}
-
-		// we're quite late already...
-		if (next_schedule < 0)
-			next_schedule = 0;
-
-	} else {//we're not allowed to sleep, there is other activity going on.
-		nsbeos_window_process_reformats();
-		block = false;
+	// compute schedule timeout
+        if (earliest_callback_timeout != B_INFINITE_TIMEOUT) {
+                next_schedule = earliest_callback_timeout - system_time();
+        } else {
+                next_schedule = earliest_callback_timeout;
         }
 
-	/*
-	LOG(("gui_poll: browser_reformat_pending:%d earliest_callback_timeout:%Ld"
-		" next_schedule:%Ld block:%d ", browser_reformat_pending,
-		earliest_callback_timeout, next_schedule, block));
-	*/
+        // we're quite late already...
+        if (next_schedule < 0)
+                next_schedule = 0;
 
 	timeout.tv_sec = (long)(next_schedule / 1000000LL);
 	timeout.tv_usec = (long)(next_schedule % 1000000LL);
 
 	//LOG(("gui_poll: select(%d, ..., %Ldus", max_fd, next_schedule));
 	fd_count = select(max_fd, &read_fd_set, &write_fd_set, &exc_fd_set, 
-		block ? NULL : &timeout);
+		&timeout);
 	//LOG(("select: %d\n", fd_count));
 
 	if (fd_count > 0 && FD_ISSET(sEventPipe[0], &read_fd_set)) {
diff --git a/beos/window.cpp b/beos/window.cpp
index 8975c1871..d27bca758 100644
--- a/beos/window.cpp
+++ b/beos/window.cpp
@@ -883,9 +883,7 @@ void nsbeos_window_resize_event(BView *view, gui_window *g, BMessage *event)
 	width++;
 	height++;
 
-
-		g->bw->reformat_pending = true;
-		browser_reformat_pending = true;
+        browser_window_schedule_reformat(g->bw);
 
 	return;
 }
@@ -901,51 +899,40 @@ void nsbeos_window_moved_event(BView *view, gui_window *g, BMessage *event)
 	//view->Invalidate(view->Bounds());
 	view->UnlockLooper();
 
-	//g->bw->reformat_pending = true;
-	//browser_reformat_pending = true;
-	
-
 	return;
 }
 
 
 void nsbeos_reflow_all_windows(void)
 {
-	for (struct gui_window *g = window_list; g; g = g->next)
-		g->bw->reformat_pending = true;
-
-	browser_reformat_pending = true;
+	for (struct gui_window *g = window_list; g; g = g->next) {
+                browser_window_schedule_reformat(g->bw);
+        }
 }
 
 
+
 /**
- * Process pending reformats
+ * callback from core to reformat a window.
  */
-
-void nsbeos_window_process_reformats(void)
+static void beos_window_reformat(struct gui_window *g)
 {
-	struct gui_window *g;
+        if (g == NULL) {
+                return;
+        }
 
-	browser_reformat_pending = false;
-	for (g = window_list; g; g = g->next) {
-		NSBrowserFrameView *view = g->view;
-		if (!g->bw->reformat_pending)
-			continue;
-		if (!view || !view->LockLooper())
-			continue;
-		g->bw->reformat_pending = false;
-		BRect bounds = view->Bounds();
-		view->UnlockLooper();
+        NSBrowserFrameView *view = g->view;
+        if (view && view->LockLooper()) {
+                BRect bounds = view->Bounds();
+                view->UnlockLooper();
 #warning XXX why - 1 & - 2 !???
-		browser_window_reformat(g->bw,
-				false,
-				bounds.Width() + 1 /* - 2*/,
-				bounds.Height() + 1);
-	}
-
+                browser_window_reformat(g->bw,
+                                        false,
+                                        bounds.Width() + 1 /* - 2*/,
+                                        bounds.Height() + 1);
+        }        
 }
 
-
 void nsbeos_window_destroy_browser(struct gui_window *g)
 {
 	browser_window_destroy(g->bw);
@@ -1356,6 +1343,7 @@ static struct gui_window_table window_table = {
 	gui_window_set_scroll,
 	gui_window_get_dimensions,
 	gui_window_update_extent,
+        beos_window_reformat,
 
 	/* from scaffold */
 	gui_window_set_title,
diff --git a/beos/window.h b/beos/window.h
index fb67517d2..0e38d88ed 100644
--- a/beos/window.h
+++ b/beos/window.h
@@ -51,7 +51,6 @@ void nsbeos_dispatch_event(BMessage *message);
 
 
 void nsbeos_reflow_all_windows(void);
-void nsbeos_window_process_reformats(void);
 
 nsbeos_scaffolding *nsbeos_get_scaffold(struct gui_window *g);
 struct browser_window *nsbeos_get_browser_for_gui(struct gui_window *g);
diff --git a/cocoa/BrowserView.m b/cocoa/BrowserView.m
index b0042f760..2a3382c8c 100644
--- a/cocoa/BrowserView.m
+++ b/cocoa/BrowserView.m
@@ -38,7 +38,6 @@
 - (void) scrollVertical: (CGFloat) amount;
 - (CGFloat) pageScroll;
 
-+ (void)reformatTimerFired: (NSTimer *) timer;
 - (void) reformat;
 
 - (void) popUpContextMenuForEvent: (NSEvent *) event;
@@ -60,8 +59,6 @@
 
 static const CGFloat CaretWidth = 1.0;
 static const NSTimeInterval CaretBlinkTime = 0.8;
-static NSMutableArray *cocoa_reformat_pending = nil;
-
 
 - initWithFrame: (NSRect) frame;
 {
@@ -438,13 +435,7 @@ static browser_mouse_state cocoa_mouse_flags_for_event( NSEvent *evt )
 
 - (void) adjustFrame;
 {
-	browser->reformat_pending = true;
-	browser_reformat_pending = true;
-
-	if (cocoa_reformat_pending == nil) {
-		cocoa_reformat_pending = [[NSMutableArray alloc] init];
-	}
-	[cocoa_reformat_pending addObject: self];
+        browser_window_schedule_reformat(browser);
 	
 	[super adjustFrame];
 }
@@ -492,24 +483,6 @@ static browser_mouse_state cocoa_mouse_flags_for_event( NSEvent *evt )
 	browser_window_reformat( browser, false, cocoa_pt_to_px( NSWidth( size ) ), cocoa_pt_to_px( NSHeight( size ) ) );
 }
 
-+ (void)reformatTimerFired: (NSTimer *) timer;
-{
-	if (browser_reformat_pending) {
-		[cocoa_reformat_pending makeObjectsPerformSelector: @selector( reformat )];
-		[cocoa_reformat_pending removeAllObjects];
-		browser_reformat_pending = false;
-	}
-}
-
-+ (void) initialize;
-{
-	NSTimer *timer = [[NSTimer alloc] initWithFireDate: nil interval: 0.02 
-												target: self selector: @selector(reformatTimerFired:) 
-											  userInfo: nil repeats: YES];
-	[[NSRunLoop currentRunLoop] addTimer: timer forMode: NSRunLoopCommonModes];
-	[timer release];
-}
-
 - (void) popUpContextMenuForEvent: (NSEvent *) event;
 {
 	if (content_get_type( browser->current_content ) != CONTENT_HTML) return;
diff --git a/cocoa/gui.m b/cocoa/gui.m
index 713f456cd..405dab9c2 100644
--- a/cocoa/gui.m
+++ b/cocoa/gui.m
@@ -129,8 +129,20 @@ static void gui_window_set_scroll(struct gui_window *g, int sx, int sy)
 	[[(BrowserViewController *)g browserView] scrollPoint: cocoa_point( sx, sy )];
 }
 
-static void gui_window_get_dimensions(struct gui_window *g, int *width, int *height,
-							   bool scaled)
+/**
+ * callback from core to reformat a window.
+ */
+static void cocoa_window_reformat(struct gui_window *gw)
+{
+	if (gw != NULL) {
+                [[(BrowserViewController *)g browserView] reformat ];
+	}
+}
+
+
+static void gui_window_get_dimensions(struct gui_window *g,
+                                      int *width, int *height,
+                                      bool scaled)
 {
 	NSCParameterAssert( width != NULL && height != NULL );
 	
@@ -278,6 +290,7 @@ static struct gui_window_table window_table = {
 	.set_scroll = gui_window_set_scroll,
 	.get_dimensions = gui_window_get_dimensions,
 	.update_extent = gui_window_update_extent,
+        .reformat = cocoa_window_reformat,
 
 	.set_title = gui_window_set_title,
 	.set_url = gui_window_set_url,
diff --git a/desktop/browser.c b/desktop/browser.c
index 6e3ed9718..dc2db723c 100644
--- a/desktop/browser.c
+++ b/desktop/browser.c
@@ -66,14 +66,11 @@
 #include "utils/utils.h"
 #include "utils/utf8.h"
 
-/** one or more windows require a reformat */
-bool browser_reformat_pending;
 
 /** maximum frame depth */
 #define FRAME_DEPTH 8
 
 
-
 /**
  * Get position of scrollbar widget within browser window.
  *
@@ -795,7 +792,6 @@ nserror browser_window_initialise_common(enum browser_window_create_flags flags,
 	/* window characteristics */
 	bw->refresh_interval = -1;
 
-	bw->reformat_pending = false;
 	bw->drag_type = DRAGGING_NONE;
 	bw->scale = (float) nsoption_int(scale) / 100.0;
 
@@ -1623,7 +1619,13 @@ void browser_window_destroy_internal(struct browser_window *bw)
 		browser_window_destroy_children(bw);
 	}
 
+	/* clear any pending callbacks */
 	guit->browser->schedule(-1, browser_window_refresh, bw);
+	/* The ugly cast here is so the reformat function can be
+	 * passed a gui window pointer in its API rather than void*
+	 */
+	LOG(("Clearing schedule %p(%p)", guit->window->reformat, bw->window));
+	guit->browser->schedule(-1, (void(*)(void*))guit->window->reformat, bw->window);      
 
 	/* If this brower window is not the root window, and has focus, unset
 	 * the root browser window's focus pointer. */
@@ -2362,6 +2364,16 @@ void browser_window_set_pointer(struct browser_window *bw,
 	guit->window->set_pointer(root->window, gui_shape);
 }
 
+/* exported function documented in desktop/browser.h */
+nserror browser_window_schedule_reformat(struct browser_window *bw)
+{
+	/* The ugly cast here is so the reformat function can be
+	 * passed a gui window pointer in its API rather than void*
+	 */
+	LOG(("Scheduleing %p(%p)", guit->window->reformat, bw->window));
+	guit->browser->schedule(0, (void(*)(void*))guit->window->reformat, bw->window);
+	return NSERROR_OK;
+}
 
 /**
  * Reformat a browser window contents to a new width or height.
@@ -2413,8 +2425,7 @@ static void browser_window_set_scale_internal(struct browser_window *bw,
 		if (content_can_reformat(c) == false) {
 			browser_window_update(bw, false);
 		} else {
-			bw->reformat_pending = true;
-			browser_reformat_pending = true;
+			browser_window_schedule_reformat(bw);
 		}
 	}
 
diff --git a/desktop/browser.h b/desktop/browser.h
index ca99a5d16..88b757727 100644
--- a/desktop/browser.h
+++ b/desktop/browser.h
@@ -60,8 +60,6 @@ typedef enum {
 	BW_EDITOR_CAN_PASTE	= (1 << 2)	/**< Can paste, input */
 } browser_editor_flags;
 
-extern bool browser_reformat_pending;
-
 /** flags to browser_window_create */
 enum browser_window_create_flags {
 	/** No flags set */
@@ -259,6 +257,21 @@ struct browser_window *browser_window_find_target(
 		struct browser_window *bw, const char *target,
 		browser_mouse_state mouse);
 
+/**
+ * Cause the frontends reformat entry to be called in safe context.
+ *
+ * The browser_window_reformat call cannot safely be called from some
+ * contexts, this call allows for the reformat to happen from a safe
+ * top level context.
+ *
+ * The callback is frontend provided as the context information (size
+ * etc.) about the windowing toolkit is only available to the
+ * frontend.
+ */
+nserror browser_window_schedule_reformat(struct browser_window *bw);
+
+
+
 void browser_select_menu_callback(void *client_data,
 		int x, int y, int width, int height);
 
diff --git a/desktop/browser_private.h b/desktop/browser_private.h
index 339bc46ee..cbc29aaa3 100644
--- a/desktop/browser_private.h
+++ b/desktop/browser_private.h
@@ -87,9 +87,6 @@ struct browser_window {
 	/** Refresh interval (-1 if undefined) */
 	int refresh_interval;
 
-	/** Window has been resized, and content needs reformatting. */
-	bool reformat_pending;
-
 	/** Window dimensions */
 	int x;
 	int y;
diff --git a/desktop/gui.h b/desktop/gui.h
index d44b57d1c..a19f30115 100644
--- a/desktop/gui.h
+++ b/desktop/gui.h
@@ -105,7 +105,9 @@ struct gui_window_table {
 			struct gui_window *existing,
 			gui_window_create_flags flags);
 
-	/** destroy previously created gui window */
+	/**
+	 * Destroy previously created gui window
+	 */
 	void (*destroy)(struct gui_window *g);
 
 	/**
@@ -168,6 +170,17 @@ struct gui_window_table {
 	 */
 	void (*update_extent)(struct gui_window *g);
 
+	/**
+	 * Reformat a window.
+	 *
+	 * This is used to perform reformats when the page contents
+	 * require reformating. The reformat is requested using
+	 * browser_window_schedule_reformat and occours via a scheduled
+	 * callback hence from top level context.
+	 *
+	 * \param g gui_window to reformat.
+	 */
+	void (*reformat)(struct gui_window *g);
 
 
 	/* Optional entries */
diff --git a/desktop/gui_factory.c b/desktop/gui_factory.c
index fd0867491..977805e9c 100644
--- a/desktop/gui_factory.c
+++ b/desktop/gui_factory.c
@@ -154,6 +154,9 @@ static nserror verify_window_register(struct gui_window_table *gwt)
 	if (gwt->update_extent == NULL) {
 		return NSERROR_BAD_PARAMETER;
 	}
+	if (gwt->reformat == NULL) {
+		return NSERROR_BAD_PARAMETER;
+	}
 
 
 	/* fill in the optional entries with defaults */
diff --git a/framebuffer/gui.c b/framebuffer/gui.c
index 0632bf3c6..727319f0f 100644
--- a/framebuffer/gui.c
+++ b/framebuffer/gui.c
@@ -1758,6 +1758,15 @@ gui_window_remove_caret(struct gui_window *g)
 	}
 }
 
+static void nsgtk_window_reformat(struct gui_window *gw)
+{
+	/** @todo if we ever do zooming reformat should be implemented */
+	LOG(("window:%p", gw));
+
+	/*
+	  browser_window_reformat(gw->bw, false, width, height);
+	*/
+}
 
 static struct gui_window_table framebuffer_window_table = {
 	.create = gui_window_create,
@@ -1768,6 +1777,7 @@ static struct gui_window_table framebuffer_window_table = {
 	.set_scroll = gui_window_set_scroll,
 	.get_dimensions = gui_window_get_dimensions,
 	.update_extent = gui_window_update_extent,
+	.reformat = framebuffer_window_reformat,
 
 	.set_url = gui_window_set_url,
 	.set_status = gui_window_set_status,
diff --git a/gtk/gui.c b/gtk/gui.c
index 9cd89e627..bb83721fe 100644
--- a/gtk/gui.c
+++ b/gtk/gui.c
@@ -518,11 +518,6 @@ static void nsgtk_poll(bool active)
 
 	schedule_run();
 
-	if (browser_reformat_pending) {
-		nsgtk_window_process_reformats();
-		block = false;
-	}
-
 	gtk_main_iteration_do(block);
 
 	for (unsigned int i = 0; i != fd_count; i++) {
diff --git a/gtk/window.c b/gtk/window.c
index a3d6d4936..d1cd6b1a5 100644
--- a/gtk/window.c
+++ b/gtk/window.c
@@ -638,9 +638,7 @@ static gboolean nsgtk_window_size_allocate_event(GtkWidget *widget,
 {
 	struct gui_window *g = data;
 
-	g->bw->reformat_pending = true;
-	browser_reformat_pending = true;
-
+	browser_window_schedule_reformat(g->bw);
 
 	return TRUE;
 }
@@ -854,35 +852,24 @@ gui_window_create(struct browser_window *bw,
 void nsgtk_reflow_all_windows(void)
 {
 	for (struct gui_window *g = window_list; g; g = g->next) {
-		nsgtk_tab_options_changed(
-				nsgtk_scaffolding_notebook(g->scaffold));
-		g->bw->reformat_pending = true;
+		nsgtk_tab_options_changed(nsgtk_scaffolding_notebook(g->scaffold));
+		browser_window_schedule_reformat(g->bw);
 	}
-
-	browser_reformat_pending = true;
 }
 
 
 /**
- * Process pending reformats
+ * callback from core to reformat a window.
  */
-
-void nsgtk_window_process_reformats(void)
+static void nsgtk_window_reformat(struct gui_window *gw)
 {
-	struct gui_window *g;
 	GtkAllocation alloc;
 
-	browser_reformat_pending = false;
-	for (g = window_list; g; g = g->next) {
-		if (!g->bw->reformat_pending)
-			continue;
+	if (gw != NULL) {
+		/** @todo consider gtk_widget_get_allocated_width() */
+		nsgtk_widget_get_allocation(GTK_WIDGET(gw->layout), &alloc);
 
-		g->bw->reformat_pending = false;
-
-		/* @todo consider gtk_widget_get_allocated_width() */
-		nsgtk_widget_get_allocation(GTK_WIDGET(g->layout), &alloc);
-
-		browser_window_reformat(g->bw, false, alloc.width, alloc.height);
+		browser_window_reformat(gw->bw, false, alloc.width, alloc.height);
 	}
 }
 
@@ -1242,6 +1229,7 @@ static struct gui_window_table window_table = {
 	.set_scroll = gui_window_set_scroll,
 	.get_dimensions = gui_window_get_dimensions,
 	.update_extent = gui_window_update_extent,
+	.reformat = nsgtk_window_reformat,
 
 	.set_icon = gui_window_set_icon,
 	.set_status = gui_window_set_status,
diff --git a/gtk/window.h b/gtk/window.h
index e4a4fda6a..01345b993 100644
--- a/gtk/window.h
+++ b/gtk/window.h
@@ -36,7 +36,6 @@ struct browser_window *nsgtk_get_browser_window(struct gui_window *g);
 nsgtk_scaffolding *nsgtk_get_scaffold(struct gui_window *g);
 GdkPixbuf *nsgtk_get_icon(struct gui_window *gw);
 void nsgtk_reflow_all_windows(void);
-void nsgtk_window_process_reformats(void);
 float nsgtk_get_scale_for_gui(struct gui_window *g);
 int nsgtk_gui_window_update_targets(struct gui_window *g);
 void nsgtk_window_destroy_browser(struct gui_window *g);
diff --git a/monkey/browser.c b/monkey/browser.c
index e61d6deb3..0e488c578 100644
--- a/monkey/browser.c
+++ b/monkey/browser.c
@@ -64,19 +64,13 @@ monkey_find_window_by_content(hlcache_handle *content)
   return ret;
 }
 
-void
-monkey_window_process_reformats(void)
+
+/**
+ * callback from core to reformat a window.
+ */
+static void monkey_window_reformat(struct gui_window *gw)
 {
-  RING_ITERATE_START(struct gui_window, gw_ring, c_ring) {
-    if (c_ring == NULL)
-      RING_ITERATE_STOP(gw_ring, c_ring);
-    if (c_ring->bw->reformat_pending) {
-      browser_window_reformat(c_ring->bw,
-                              false,
-                              c_ring->width,
-                              c_ring->height);
-    }
-  } RING_ITERATE_END(gw_ring, c_ring);
+	browser_window_reformat(gw->bw,	false, gw->width, gw->height);
 }
 
 void
@@ -511,6 +505,7 @@ static struct gui_window_table window_table = {
 	.set_scroll = gui_window_set_scroll,
 	.get_dimensions = gui_window_get_dimensions,
 	.update_extent = gui_window_update_extent,
+	.reformat = monkey_window_reformat,
 
 	.set_title = gui_window_set_title,
 	.set_url = gui_window_set_url,
diff --git a/monkey/poll.c b/monkey/poll.c
index d5b49f059..e65f2d3e2 100644
--- a/monkey/poll.c
+++ b/monkey/poll.c
@@ -126,11 +126,6 @@ monkey_poll(bool active)
 
   schedule_run();
 
-  if (browser_reformat_pending) {
-    monkey_window_process_reformats();
-    block = false;
-  }
-
   LOG(("Iterate %sblocking", block?"":"non-"));
   if (block) {
     fprintf(stdout, "GENERIC POLL BLOCKING\n");
diff --git a/riscos/gui.c b/riscos/gui.c
index 00f6ebc11..3253f796f 100644
--- a/riscos/gui.c
+++ b/riscos/gui.c
@@ -1864,17 +1864,18 @@ static void riscos_poll(bool active)
 	/* Poll wimp. */
 	xhourglass_off();
 	track_poll_offset = ro_mouse_poll_interval();
-	if (sched_active || (track_poll_offset > 0) ||
-			browser_reformat_pending) {
+	if (sched_active || (track_poll_offset > 0)) {
 		os_t t = os_read_monotonic_time();
 
-		if (track_poll_offset > 0)
+		if (track_poll_offset > 0) {
 			t += track_poll_offset;
-		else
+		} else {
 			t += 10;
+		}
 
-		if (sched_active && (sched_time - t) < 0)
+		if (sched_active && (sched_time - t) < 0) {
 			t = sched_time;
+		}
 
 		event = wimp_poll_idle(mask, &block, t, 0);
 	} else {
@@ -1895,9 +1896,6 @@ static void riscos_poll(bool active)
 	}
 
 	ro_gui_window_update_boxes();
-
-	if (browser_reformat_pending && event == wimp_NULL_REASON_CODE)
-		ro_gui_window_process_reformats();
 }
 
 
diff --git a/riscos/gui.h b/riscos/gui.h
index bc59b5db9..3403f551e 100644
--- a/riscos/gui.h
+++ b/riscos/gui.h
@@ -134,7 +134,6 @@ void ro_gui_window_iconise(struct gui_window *g,
 bool ro_gui_toolbar_dataload(struct gui_window *g, wimp_message *message);
 void ro_gui_window_redraw_all(void);
 void ro_gui_window_update_boxes(void);
-void ro_gui_window_process_reformats(void);
 void ro_gui_window_quit(void);
 /* void ro_gui_window_close_all(void); */
 #define ro_gui_window_close_all ro_gui_window_quit  /* no need for a separate fn */
diff --git a/riscos/window.c b/riscos/window.c
index 5a3369769..2ad432b2e 100644
--- a/riscos/window.c
+++ b/riscos/window.c
@@ -975,7 +975,6 @@ static void gui_window_update_extent(struct gui_window *g)
 	os_error		*error;
 	wimp_window_info	info;
 	wimp_window_state	state;
-	bool			update;
 	unsigned int		flags;
 
 	assert(g);
@@ -995,9 +994,8 @@ static void gui_window_update_extent(struct gui_window *g)
 		info.yscroll += scroll;
 	}
 
-	/* only allow a further reformat if we've gained/lost scrollbars */
+	/* only schedule a reformat if we've gained/lost scrollbars */
 	flags = info.flags & (wimp_WINDOW_HSCROLL | wimp_WINDOW_VSCROLL);
-	update = g->bw->reformat_pending;
 	g->update_extent = true;
 	ro_gui_window_open(PTR_WIMP_OPEN(&info));
 
@@ -1009,8 +1007,9 @@ static void gui_window_update_extent(struct gui_window *g)
 		warn_user("WimpError", error->errmess);
 		return;
 	}
-	if (flags == (state.flags & (wimp_WINDOW_HSCROLL | wimp_WINDOW_VSCROLL)))
-		g->bw->reformat_pending = update;
+	if (flags == (state.flags & (wimp_WINDOW_HSCROLL | wimp_WINDOW_VSCROLL))) {
+		browser_window_schedule_reformat(g->bw);
+	}
 }
 
 
@@ -1557,8 +1556,7 @@ void ro_gui_window_open(wimp_open *open)
 				height -= size;
 				state.visible.y0 += size;
 				if (h) {
-					g->bw->reformat_pending = true;
-					browser_reformat_pending = true;
+					browser_window_schedule_reformat(g->bw);
 				}
 			}
 			state.flags |= wimp_WINDOW_HSCROLL;
@@ -1567,8 +1565,7 @@ void ro_gui_window_open(wimp_open *open)
 				height += size;
 				state.visible.y0 -= size;
 				if (h) {
-					g->bw->reformat_pending = true;
-					browser_reformat_pending = true;
+					browser_window_schedule_reformat(g->bw);
 				}
 			}
 			state.flags &= ~wimp_WINDOW_HSCROLL;
@@ -1583,8 +1580,7 @@ void ro_gui_window_open(wimp_open *open)
 				width -= size;
 				state.visible.x1 -= size;
 				if (h) {
-					g->bw->reformat_pending = true;
-					browser_reformat_pending = true;
+					browser_window_schedule_reformat(g->bw);
 				}
 			}
 			state.flags |= wimp_WINDOW_VSCROLL;
@@ -1593,8 +1589,7 @@ void ro_gui_window_open(wimp_open *open)
 				width += size;
 				state.visible.x1 += size;
 				if (h) {
-					g->bw->reformat_pending = true;
-					browser_reformat_pending = true;
+					browser_window_schedule_reformat(g->bw);
 				}
 			}
 			state.flags &= ~wimp_WINDOW_VSCROLL;
@@ -1607,8 +1602,7 @@ void ro_gui_window_open(wimp_open *open)
 		if ((g->old_width > 0) && (g->old_width != width) &&
 				(ro_gui_ctrl_pressed()))
 			new_scale = (g->bw->scale * width) / g->old_width;
-		g->bw->reformat_pending = true;
-		browser_reformat_pending = true;
+		browser_window_schedule_reformat(g->bw);
 	}
 	if (g->update_extent || g->old_width != width ||
 			g->old_height != height) {
@@ -4379,25 +4373,17 @@ void ro_gui_window_update_boxes(void)
 
 
 /**
- * Process pending reformats
+ * callback from core to reformat a window.
  */
-
-void ro_gui_window_process_reformats(void)
+static void riscos_window_reformat(struct gui_window *gw)
 {
-	struct gui_window *g;
-
-	browser_reformat_pending = false;
-	for (g = window_list; g; g = g->next) {
-		if (!g->bw->reformat_pending)
-			continue;
-		g->bw->reformat_pending = false;
-		browser_window_reformat(g->bw, false,
-				g->old_width / 2,
-				g->old_height / 2);
+	if (gw != NULL) {
+		browser_window_reformat(gw->bw, false,
+					gw->old_width / 2,
+					gw->old_height / 2);
 	}
 }
 
-
 /**
  * Destroy all browser windows.
  */
@@ -5174,6 +5160,7 @@ static struct gui_window_table window_table = {
 	.set_scroll = gui_window_set_scroll,
 	.get_dimensions = gui_window_get_dimensions,
 	.update_extent = gui_window_update_extent,
+	.reformat = riscos_window_reformat,
 
 	.set_title = gui_window_set_title,
 	.set_url = gui_window_set_url,
diff --git a/windows/gui.c b/windows/gui.c
index 824abade7..19a31c1be 100644
--- a/windows/gui.c
+++ b/windows/gui.c
@@ -93,7 +93,6 @@ static void nsws_set_scale(struct gui_window *gw, float scale)
 		return;
 
 	browser_window_set_scale(gw->bw, scale, true);
-	browser_window_reformat(gw->bw, false, gw->width, gw->height);
 }
 
 
@@ -1820,6 +1819,16 @@ nsws_create_main_class(HINSTANCE hinstance) {
 	return ret;
 }
 
+/**
+ * callback from core to reformat a window.
+ */
+static void win32_window_reformat(struct gui_window *gw)
+{
+	if (gw != NULL) {
+		browser_window_reformat(gw->bw, false, gw->width, gw->height);
+	}
+}
+
 /**
  * Generate a windows path from one or more component elemnts.
  *
@@ -2087,6 +2096,7 @@ static struct gui_window_table window_table = {
 	.set_scroll = gui_window_set_scroll,
 	.get_dimensions = gui_window_get_dimensions,
 	.update_extent = gui_window_update_extent,
+	.reformat = win32_window_reformat,
 
 	.set_title = gui_window_set_title,
 	.set_url = gui_window_set_url,