1766862 - Blurry font rendering with fractional scaling on Ubuntu 22.04 xwayland builds

Status: RESOLVED WONTFIX

(Core :: Widget: Gtk, defect, P3)

Description

[Ryan VanderMeulen [:RyanVM]]

Attachment: screenshot with and without fractional scaling

I recently updated to Ubuntu 22.04 and my 99.0.1 snap build has much blurrier font rendering than it used to have. I have 200% scaling set and fractional scaling toggled. In the attached screenshot, the rendering I see is on the left. When I un-toggle fractional scaling (leaving 200% scaling still enabled), the fonts are much clearer as shown on the right.

I also checked the 100.0b9 build with wayland enabled by default and font rendering is clear with fractional scaling toggled, so maybe an issue between xwayland and snap builds?

Comment 1

[Ryan VanderMeulen [:RyanVM]]

Olivier, have you seen any other reports along these lines?

Comment 2

[Olivier Tilloy]

Yes, this very issue was mentioned to me a couple of times in the last week or so. I don't use fractional scaling myself, so I haven't experienced it firsthand.
I guess this is one solid argument in favour of enabling native wayland support.

Comment 3

[Ryan VanderMeulen [:RyanVM]]

Seems possibly-related to bug 1765020 just going off the description.

Comment 4

[:gerard-majax]

Ryan, I can't repro that on a VM, do you still experience this?

Comment 5

[Ryan VanderMeulen [:RyanVM]]

Yes

Comment 6

[:gerard-majax]

Can you share more details on your setup? And the website that repro?

Comment 7

[:gerard-majax]

Ok now I repro:

• only on stable (because XWayland)
• 1920x1080, fractional scaling set, 125% selected.

As soon as I move to a wayland version, keeping the screen settings does not result in a blurry UI. Also, it's not just the fonts, it's the whole firefox that is blurry.

Comment 8

[:gerard-majax]

Firefox is now defaulting to Wayland on release since 121. As this bug is a limitation of XWayland, we cannot fix it.