This bug been identified as part of Chrome's flake reduction initiative. Resolution of this issue is critical because it has a large impact on the stability of Chrome CI/CQ. Resolving these issues will be essential to meet Chrome’s flake reduction goals.

This bug has led to a large number of gardened builds failing in the last 7 days. List of gardened build failures caused by this cluster can be viewed at:
https://data.corp.google.com/sites/chrome_generic_flakiness_dashboard_datasite/build_failures/?av=rpqxzw:ktu56&fb=is_sheriff_or_cq_builder:eq:true&f=cluster_name:in:b%2F400617105
or in LUCI Analysis and grouped by builders:
https://luci-milo.appspot.com/ui/tests/p/chromium/rules/3519deb73451d0c9b91241ccea2406fa?tab=recent-failures&filterToMetric=builds-failed-due-to-flaky-tests&groupBy=builder&orderBy=invocationFailures

Please consider the following strategies to mitigate the impact from this issue which are rated in order of resolution preference:
1. Resolve the underlying test issue.
2. Move the flaky test from Critical Builders to FYI Builder
3. Disable test (least desirable as it reduces test coverage) and add a Test-Disabled label to this issue. The disabled tests might continue running in reviver builders (go/test-reviver), see config [1] for a list of supported builders.

http://go/resolve-chrome-top-flakes provides more information on the tools available for resolving flaky tests.

When investigating this failure, you may identify this bug is too broad (encompasses multiple different issues) or too narrow (only captures one part of a larger issue). If this applies, you can combine issues[2]  or split issues[3].

Links:
[1] https://source.chromium.org/chromium/chromium/src/+/main:infra/config/subprojects/reviver/reviver.star
[2] https://luci-analysis.appspot.com/help#combining-issues
[3] https://luci-analysis.appspot.com/help#splitting-issues

Why LUCI Analysis posted this comment: https://luci-milo.appspot.com/ui/tests/help#policy-activated (Policy ID: builds-failed-due-to-flaky-tests)

I'm seeing the same thing within my organization.

looks like a bug fix was released for this for service now- the issue is happened in both edge and chrome updates to the chromium browsers.

Description
Chrome version 131 and Microsoft Edge version 131 have introduced an issue related to text selection, which can lead to confusion when copy and pasting. When experiencing the issue, highlighted text will not appear highlighted.
Although copying and pasting still works, the text will not appear highlighted.
Fixed in: Washington DC Patch 9 and Xanadu.
Steps to Reproduce
 
Login to any instance
Use Microsoft Edge version 131
Open any ticket(incident, change, request)
Use any method to copy & paste text.  (use ctrl c, ctrl v or right click to copy & paste text)
Expected: Text is copied or pasted
Actual:  Nothing happens
Workaround
SerciceNow has provided a fix in Washington DC Patch9 and Xanadu.
If it is not possible to upgrade to any of these versions, please import the attached UI script to the affected instances.
Note: Please ensure to remove the UI Script after you upgrade to one of the fixed versions.

Related Problem: PRB1723262

Tested the  issue on latest chrome version #131.0.6778.70 using Windows 10 as per steps in c#1

Steps:
=====
1) Launch chrome
2) Navigate to wikipedia.org
3) Select the text then copy and paste the text

Observed that “able to copy and paste the selected text”

@Reporter: Could you please review the attached screencast and let us know if we missed anything from our end. Also please check this issue on fresh chrome profile without any apps/extensions

Attaching screencast for reference

Thanks..!