We may be able to do this on backend with #21443. I think it's certainly better to do it there to avoid content flashes. If we want to keep date formatting in frontend, there is the option of #21429 which I devised.

I read both PRs you linked. About the following comment:

    `requestAnimationFrame` is the proper way to mutate DOM without flicker. It can and should be avoided. It's just sloppiness on GitHub's side that they still have these flickers.

    I will also move all stuff in [formatting.js](https://github.com/yardenshoham/gitea/blob/main/web_src/js/features/formatting.js) into this script as well. These are all critical replacements.

Originally posted by @silverwind in #21429 (comment)

If you are still doing that then it's worth merging this as it's simply building on

• Respect user's locale when rendering the date range in the repo activity page #21410

Any solution of a different implementation would still have to include this JS so I suggest merging this for now

#21410 did this for the activity page, this just does it for all other timestamps, easy win

If we decide for the JS solution, we can certainly go ahead with this already.

• I'm hoping to merge this, I believe having better datetime localization is a big plus even if it comes with a lightweight flicker. The work on Replace inline script for critical JS with standalone script #21429 can keep going, this doesn't hinder it at all

make L-G-T-M work