Made it illegal/assert when io.DisplayTime == 0.0f (with an exception for the first frame). ...

Causing too many subtle side-effect, e.g. IsNavInputPressed() would return true multiple times in a row.

Demo: Added Auto-Scroll option in Log/Console. Comments. Removed some ImColor() uses.

Font: Moved functions to internal block (not enforced). Made ConfigData pointer const. Added link to stb's notes.

Font: Fixed high-level ImGui::CalcTextSize() used by most widgets from erroneously subtracting 1.0f*scale to calculated text width. Among noticeable side-effects, it would make sequences of repeated Text/SameLine calls not align the same as a single call, and create mismatch between high-level size calculation and those performed with the lower-level ImDrawList api. (#792)

ImDrawData: Added FramebufferScale field (currently a copy of the value from io.DisplayFramebufferScale). ...

This is to allow render functions being written without pulling any data from ImGuiIO, allowing incoming multi-viewport feature to behave on Retina display and with multiple displays. If you are not using a custom binding, please update your render function code ahead of time, and use draw_data->FramebufferScale instead of io.DisplayFramebufferScale. (#2306, #1676)
Examples: Metal, OpenGL2, OpenGL3: Fixed offsetting of clipping rectangle with ImDrawData::DisplayPos != (0,0) when the display frame-buffer scale scale is not (1,1). While this doesn't make a difference when using master branch, this is effectively fixing support for multi-viewport with Mac Retina Displays on those examples. (#2306) Also using ImDrawData::FramebufferScale instead of io.DisplayFramebufferScale.
Examples: Clarified the use the ImDrawData::DisplayPos to offset clipping rectangles.

Window: Fixed initial width of collapsed windows not taking account of contents width (broken in 1.67). (#2336, #176)

Minor tweaks to reduce false positive of PVS Studio static analyzer.

Menus: Tweaked horizontal overlap between parent and child menu (to help convey relative depth) from using style.ItemSpacing.x to style.ItemInnerSpacing.x, the later being expected to be smaller. (#1086)

Added IsItemActivated() as an extension to the IsItemDeactivated/IsItemDeactivatedAfterEdit functions which are useful to implement variety of undo patterns. (#820, #956, #1875)

Internals: EndGroup: Removed unnecesary parameter to ItemSize()

Internals: Removed unnecessary code.

Fonts: Fixed crash if FontGlobalScale is zero. Correctly debug naming default font if not 13 px. Demo: Moved PopupRounding along with other rounding values. Metrics: Displaying indexes with idx to be correct / less misleading.

Internals: Exposed internal SetWindowPos to imgui_internal.h (for imgui-test)

Removed io.DisplayVisibleMin/DisplayVisibleMax (which were marked obsolete and removed from viewport/docking branch already).

Internals: Tracking dummy select scope id (currently always zero) to facilitate merging of the range_select branch. (#1861)

Internals: Track ActiveIdHasBeenPressed (similar to ActiveIdHasBeenEdited). This is currently mostly for the benefit of the range_select branch. (#1861)

Merged from Docking branch: Various small changes, comments, typos fixes, moved blocks. To reduce overall drift. Should be no-op.

InputText: Fixed a bug where ESCAPE would be first captured by the Keyboard Navigation code. (#2321, #787)

imgui-test: Added extra item info callbacks. Using nav_bb for interactions when possible. Comments, Demo tweaks.

ImStrncpy: Fixed -Wstringop-truncation warning on GCC8 (#2323)

Fixed CloseCurrentPopup() on a child-menu of a modal incorrectly closing the modal. (#2308)

Silence XCode static analysis false positive (#2309)

Revert "Added PushID(size_t sz) helper (may not be useful/meaningful for non C/C++ languages)." ...

This reverts commit 20bc06a.

Nav: Removed unnecessary test (always failing).

Using IM_UNUSED() macro.

Fix various XCode and PVS-Studio static analyzer warnings (#2309)

Added PushID(size_t sz) helper (may not be useful/meaningful for non C/C++ languages).

When resizing from an edge, the border is more visible and better follow the rounded corners. Border rendering moved to RenderOuterBorders so it can be called in a different order for docking. (#1495, #822)

Fixed range-version of PushID() and GetID() not honoring the ### operator to restart from the seed value.

Internals: Tweaks. Comments about PushID/GetID public function.