Changed RenderTextEllipsis() logic to not trim trailing blanks before the ellipsis. (#9229)

docs/CHANGELOG.txt

diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt
index 69da227..63b22da 100644
--- a/docs/CHANGELOG.txt
+++ b/docs/CHANGELOG.txt
@@ -171,6 +171,9 @@
       end of a line rather than at the beginning of next line. (#8990, #3237)
   - Fixed low-level word-wrapping function reading from *text_end when passed
     a string range. (#9107) [@achabense]
+  - Changed RenderTextEllipsis() logic to not trim trailing blanks before
+    the ellipsis, making ellipsis position more consistent and not arbitrary
+    hiding the possibility of multiple blanks. (#9229)
 - Nav:
   - Fixed remote/shortcut InputText() not teleporting mouse cursor when
     nav cursor is visible and `io.ConfigNavMoveSetMousePos` is enabled.

imgui.cpp

diff --git a/imgui.cpp b/imgui.cpp
index e24c196..63c6789 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -3905,13 +3905,7 @@
 
         // We can now claim the space between pos_max.x and ellipsis_max.x
         const float text_avail_width = ImMax((ImMax(pos_max.x, ellipsis_max_x) - ellipsis_width) - pos_min.x, 1.0f);
-        float text_size_clipped_x = font->CalcTextSizeA(font_size, text_avail_width, 0.0f, text, text_end_full, &text_end_ellipsis).x;
-        while (text_end_ellipsis > text && ImCharIsBlankA(text_end_ellipsis[-1]))
-        {
-            // Trim trailing space before ellipsis (FIXME: Supporting non-ascii blanks would be nice, for this we need a function to backtrack in UTF-8 text)
-            text_end_ellipsis--;
-            text_size_clipped_x -= font->CalcTextSizeA(font_size, FLT_MAX, 0.0f, text_end_ellipsis, text_end_ellipsis + 1).x; // Ascii blanks are always 1 byte
-        }
+        const float text_size_clipped_x = font->CalcTextSizeA(font_size, text_avail_width, 0.0f, text, text_end_full, &text_end_ellipsis).x;
 
         // Render text, render ellipsis
         RenderTextClippedEx(draw_list, pos_min, pos_max, text, text_end_ellipsis, &text_size, ImVec2(0.0f, 0.0f));