[User Experience] Improved UX for the percentile selector

[paulb-elastic]

When changing the percentile selector in the User Experience app, it will change certain values on the page (but does not affect all data being shown).

We are looking for a better user experience so that it is clear which values are being shown relative to the percentile that is being changed. This may include moving the percentile selector (also considering if there are other apps where we may do something similar).

Changing the percentile selector will change:

• Page load duration (Backend and Frontend, but not Page Views
• User experience metrics (all)
• Core web vitals metrics (all)
• URL filter (where we show the Page load duration)
• (TBC) Page load duration by region (map) – currently showing average, but will match the percentile selector (depends on [Maps] use percentiles to generate range bands #78790)

cc @drewpost @elastic/observability-design

[drewpost]

Question - it only impacts the single value shown on the Core Vitals panel, right? The underlying "thermometer" doesn't change as it's already showing the distribution of performances. Right? cc @paulb-elastic

[paulb-elastic]

Yes @drewpost, good point. I've updated the description and the screen shot to clarify that.

[formgeist]

Isn't it the plan to do away with the core web vitals single values? Any reason not to do this now to avoid confusion?

[elasticmachine]

Pinging @elastic/uptime (Team:uptime)

[paulb-elastic]

This has been done.