886198 - HiDPI caused boxes with splitters to resize with layout.css.devPixelsPerPx != 1

Status: NEW

(Core :: Layout, defect)

Description

[A Capesius]

Attachment: xulrunner example of splitter hidpi issue

With layout.css.devPixelsPerPx set to 1.25, moving splitters causes the content in the box to slowly shrink in width. The parent box size remains constant. Persistence data is saved correctly and the box will be correct when the app is reloaded in Firefox, but the visual representation shrinks and is not correct until restart. The effect is most noticeable if you make multiple small changes in the splitter positions in the same direction, releasing the mouse each time. The right side on box3 moves left on each splitter change. Appears to be accumulated errors introduced due to rounding.