Tables: do not show empty tooltip when user submits TableHeader with no label to display. (#6342)

docs/CHANGELOG.txt

@@ -42,6 +42,8 @@ Breaking changes:
 
 Other changes:
 
+- Tables: Fixed a small miscalculation in TableHeader() leading to an empty tooltip
+  showing when a sorting column has no visible name. (#6342) [@lukaasm]
 - Backends: Clear bits sets io.BackendFlags on backend Shutdown(). (#6334, #6335] [@GereonV]
   Potentially this would facilitate switching runtime backend mid-session.
 

imgui_tables.cpp

@@ -3007,7 +3007,7 @@ void ImGui::TableHeader(const char* label)
     }
 
     // Sort order arrow
-    const float ellipsis_max = cell_r.Max.x - w_arrow - w_sort_text;
+    const float ellipsis_max = ImMax(cell_r.Max.x - w_arrow - w_sort_text, label_pos.x);
     if ((table->Flags & ImGuiTableFlags_Sortable) && !(column->Flags & ImGuiTableColumnFlags_NoSort))
     {
         if (column->SortOrder != -1)