1976082 - The strikethrough line in Bugzilla's links to closed bugs disappears when the site is zoomed in

Status: NEW

(Core :: Graphics: Text, defect)

Description

[eclaudiu64]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:142.0) Gecko/20100101 Firefox/142.0

Steps to reproduce:

A number that is a link has a line through it, as if it has been deleted, but when the site is zoomed in, that line no longer appears. Here on Bugzilla I noticed this. In Chrome I see that it appears fine and that line around the text and numbers does not disappear.

Comment 1

[eclaudiu64]

Attachment: VID_20250707220422412.mp4

Comment 2

[Jonathan Kew [:jfkthame]]

We should be snapping the text-decoration line to device pixels to ensure that it remains visible, but I suspect this isn't interacting well with pinch-zoom scaling.

I assume the same problem affects other decorations (underline and overline) as well. Does it also affect borders? (Probably.)

Comment 3

[Jonathan Kew [:jfkthame]]

Attachment: Screen Recording 2025-07-10 at 12.09.29.mov

Screen recording (from Nightly on macOS) showing how text-decoration lines and box borders don't interact well with pinch-zoom. The lines here are nominally 0.1px, so should "snap" to 1 device pixel hairlines, but during pinch-zoom they flicker erratically as the separate edges of the rects jump between pixels.

The "disappearing" line in the original report is presumably a case where the top and bottom edges ended up jumping to the same pixel boundary at a particular zoom level.