2.53 LTS is about to go EOL so we are looking to move to 3.5 LTS.

Here is the old /alerts UI from 2.53.
(Sorry, I have had to redact much of the text.)

The old user interface was perfect. We often hit this page when dancing in production because it provided us with a fast and readable overview.

Here is the new /alerts UI from 3.5.
Same browser viewport dimensions.

Look at the two thumbnails side-by-side. The loss of label density here is stark. All the information we could previously see so easily at one glance is now gone -- it has been replaced with endless scrolling.

We seldom encounter any regressions in core Prom functionality. Perf is great. The TSDB is more or less bulletproof. These unnecessary UI changes are the only black mark on your otherwise spotless releases. (I had previously sent feedback on similarly misguided changes to the Alertmanager user interface. Both that change and this one seem to have been made without giving any consideration to how users interact with the software.)

Please exercise more restraint with UI changes. There is no need to fix what ain't broken.
(What improvement did this change bring? What was the practical justification for the change?)