MUI Text flickers on firefox

[gmzacharydovel]

Steps to reproduce

Steps:

1. Setup MUI
   2.Notice the text flickers when opening things like a Select
   3.Notice if you use the virtualization examples on the MUI documentation, things flicker like crazy

Current behavior

Text seems to be arbitrarily reloaded. Setting the font with a css important override seems to help somewhat

Expected behavior

The text shouldn't flicker

Context

No response

Your environment

npx @mui/envinfo

  Don't forget to mention which browser you used.
  Output from `npx @mui/envinfo` goes here.

Search keywords: font flicker

[gmzacharydovel]

Sorry for making this while researching. I'm trying to get a minimal repro. I'll add a video of whats happening. The parent elements don't seem to be having a rerender. I think the fonts are being fully reloaded and I have no idea why. It makes me look a bit like an idiot with MUI, and I haven't seen it before.

Screen.Recording.2025-04-12.at.11.16.55.mov

[gmzacharydovel]

Is there an obvious reason for this form the MUI team?

[ZeeshanTamboli]

Is there an obvious reason for this form the MUI team?

@gmzacharydovel There's no obvious reason for this on MUI’s side — the components themselves don’t trigger that kind of re-render. A minimal reproduction would really help us investigate further.