342ms regex compile in mozilla.components.support.utils.WebURLFinder

[acreskeyMoz]

When starting to type into the URL bar, a long regex compile is seen on the main Java thread.

342ms via the Gecko Profiler timeline on Pixel 3:
https://perfht.ml/2Sg0THi

kotlin.text.Regex.<init>()
mozilla.components.support.utils.WebURLFinder.<clinit>()
org.mozilla.fenix.utils.ClipboardHandler.getUrl()
org.mozilla.fenix.search.SearchFragment.onResume()
androidx.fragment.app.Fragment.performResume()
androidx.fragment.app.FragmentManager.moveToState()
androidx.fragment.app.FragmentManager.moveFragmentToExpectedState()
androidx.fragment.app.FragmentManager.moveToState()
androidx.fragment.app.FragmentManager.executeOpsTogether()
...

(I downloaded Firefox Preview from the PlayStore, Feb 10).

This looks to be related to this issue:
#5384

Perhaps this can be done before the user interacts with the URL bar?

┆Issue is synchronized with this Jira Task

[mcomella]

Can we remove the WebURLFinder class to prevent this from happening again?

[csadilek]

@acreskeyMoz Thanks for filing. This was already fixed by Will in #5594.

It looks like you tested this on "Firefox Preview" (not Firefox Preview Nightly) which doesn't have the fix yet (it landed in A-C 29.0.0 and the latest stable Preview uses A-C 28.0.x).

@mcomella This didn't happen again :). There just wasn't a release since. There's a follow up to remove the strict URL checking: #5680

I am closing this, but please re-open if you still see this. I just verified on master that the slow regex is no longer compiled when typing the URL bar.

[acreskeyMoz]

I'm not seeing this issue on master either, thanks for looking into it.