Docking: Comments + maiintain LastFrameFocused per node + using bitfiield for docking bools.

Docking: Added context menu option to hide the tab bar of single-window dock nodes, similar to Unreal. (#2109)

Merge branch 'viewport' into docking ...

# Conflicts:
#	docs/CHANGELOG.txt
#	imgui.cpp
#	imgui_internal.h

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/imgui_impl_sdl.cpp

Examples: SDL: changed the signature of ImGui_ImplSDL2_ProcessEvent() to use a const SDL_Event*. (#2187)

Viewport: Added support for minimized window which caused problem when ImGuiBackendFlags_HasMouseHoveredViewport was not supported. (#1542) + todo

Version 1.67 WIP

Merge branch 'viewport' into docking ...

# Conflicts:
#	docs/CHANGELOG.txt
#	imgui_widgets.cpp

Merge branch 'master' into viewport ...

# Conflicts:
#	imgui.cpp

Version 1.66

Examples: SDL2+Vulkan: Fixed application shutdown which could deadlock on Linux + Xorg. (#2181)

Nav: Fixed explicit directional input not re-highlighting current nav item if there is a single item in the window and highlight has been previously disabled by the mouse. (#787)

Merge branch 'viewport' into docking ...

# Conflicts:
#	examples/example_allegro5/main.cpp
#	examples/example_marmalade/main.cpp

Merge branch 'master' into viewport + comments ...

# Conflicts:
#	examples/imgui_impl_opengl3.cpp
#	imgui.cpp

Nav: Fixed an assert in certain circumstance (mostly when using popups) when mouse positions stop being valid. (#2168) + adding a else block to make NavCalcPreferredRefPos() more explicit.

Examples: OpenGL3: Added support for GL 4.5's glClipControl(GL_UPPER_LEFT). (#2186)

Update README.md

Merge branch 'master' into viewport + specific changes for GLFW callbacks ...

# Conflicts:
#	examples/example_glfw_opengl3/main.cpp
#	examples/example_win32_directx11/main.cpp
#	examples/example_win32_directx9/main.cpp
#	examples/imgui_impl_glfw.cpp

Examples: GLFW: User previously installed GLFW callbacks are now saved and chain-called by the default callbacks. (#1759)

Examples: OpenGL3+GLFW/SDL: Made main.cpp compile with IMGUI_IMPL_OPENGL_LOADER_CUSTOM (may be missing init). (#2178)

Merge branch 'viewport' into docking

Merge branch 'master' into viewport

ListBox(): Fixed frame sizing when items_count==1 unnecessarily showing a scrollbar. (#2173). Tweaked frame sizing so list boxes will look more consistent when FramePadding is far from ItemSpacing.

Internals: Moved the FocusableItemUnregister() outside of InputScalarAsWidgetReplacement(), it should not be here and doesn't facilitate reusing InputScalarAsWidgetReplacement(). (cc #2155)

Merge branch 'viewport' into docking ...

# Conflicts:
#	imgui_demo.cpp

Merge branch 'master' into viewport ...

# Conflicts:
#	imgui.cpp

Demo: Split the contents of ShowDemoWindow() into smaller functions as it appears to speed up link time with VS. (#2152)

SliderAngle: Added optional `format` argument to allow users customize precision and make localization. (#2150)

Fixed OpenGL texture loading example in comment + Discourse link to root of discourse

Misc comments improvements