User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:81.0) Gecko/20100101 Firefox/81.0

Steps to reproduce:

Login to FamilySearch.org (Accounts are free)
load this url:
https://www.familysearch.org/tree/person/sources/KWZ3-J32
press <ctrl>F to find-in-page
In the search field type: seal

Actual results:

The text in the search field turns red indicating that the search text does not occur on the page.

Expected results:

The viewport should jump to the location of the search string and color the text green.

Note that searching for: "eal" or "temple sealing" is successful.

A mozregression session showed that this problem started with the fix for bug 1654270.

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.

Huh, interesting edge case, thanks for filing!

Set release status flags based on info from the regressing bug 1654270

Backed out for perma failures.

Push with failure: https://treeherder.mozilla.org/#/jobs?repo=autoland&selectedTaskRun=O_2GknnlTgOgBMM1yk-3QQ.0&resultStatus=pending%2Crunning%2Csuccess%2Ctestfailed%2Cbusted%2Cexception&searchStr=windows%2C7%2Copt%2Cmochitests%2Ctest-windows7-32%2Fopt-mochitest-browser-chrome-e10s%2Cbc5&revision=0d8222cd72dccaa138dfb48f17e5e7e7f81fef2c

Log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=313583154&repo=autoland&lineNumber=3632

Backout: https://hg.mozilla.org/integration/autoland/rev/694e4acf76559200c88b27a474f7d8782c455a04

[Tracking Requested - why for this release]: Annoying find-in-page regression that other users have found too.

https://hg.mozilla.org/mozilla-central/rev/dd7fb8f29da2

The patch landed in nightly and beta is affected.
:emilio, is this bug important enough to require an uplift?
If not please set status_beta to wontfix.

For more information, please visit auto_nag documentation.

Comment on attachment 9170919 [details]
Bug 1659897 - Rewind if needed when hitting a forced break in find-in-page. r=jfkthame

Beta/Release Uplift Approval Request

• User impact if declined: Somewhat odd find-in-page failures.
• Is this code covered by automated tests?: Yes
• Has the fix been verified in Nightly?: Yes
• Needs manual test from QE?: Yes
• If yes, steps to reproduce: see test-case attached to the bug, also comment 0.
• List of other uplifts needed: None
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): Relatively small change to find-in-page code, which is well covered by tests generally.
• String changes made/needed: none

Comment on attachment 9170919 [details]
Bug 1659897 - Rewind if needed when hitting a forced break in find-in-page. r=jfkthame

Approved for 81.0b5.

https://hg.mozilla.org/releases/mozilla-beta/rev/fe5bb142d4b6

Confirmed as verified fixed on latest Nightly 82.0a1 (20200831215215) on Windows 10 x64bit and MacOS 10.14.6.

Also confirmed as verified fixed on latest Beta 81.0b5 (20200901203141) on Windows 10 x64bit and MacOS 10.14.6.