- Begin() [old 5 args version] -> use Begin() [3 args], use SetNextWindowSize() SetNextWindowBgAlpha() if needed
- IsRootWindowOrAnyChildHovered() -> use IsWindowHovered(ImGuiHoveredFlags_RootAndChildWindows)
- AlignFirstTextHeightToWidgets() -> use AlignTextToFramePadding();
- SetNextWindowPosCenter() -> use SetNextWindowPos() with a pivot of (0.5f, 0.5f)
- ImFont::Glyph -> use ImFontGlyph
If you were still using the old names, read "API Breaking Changes" section of imgui.cpp to find out the new names or equivalent features, or see how they were implemented until 1.73.
If you were conveniently using the imgui copy of those STB headers in your project, you will have to update your include paths.
The reason for this change is to avoid conflicts for projects that may also be importing their own copy of the STB libraries. Note that imgui's copy of stb_textedit.h is modified.