Tab group not inherited from some extension windows when left-clicking links (Linux)

[wknapik]

Description

When opening a new tab via a link in a grouped tab, the new tab is added to the same tab group as the one with the link.

This appears to break under some circumstances with extension tabs as the source. I tested this with the extension called "Slick RSS". Left clicking on links in the extension window opens tabs that don't belong to any group, but middle-clicking does work as expected.

I see this behavior across latest Brave/Chromium/Chrome versions. Not sure if that means I should report it to Chromium and skip the report for Brave. Chromium is not on Github, so it's quite inconvenient to report to them.

Steps to Reproduce

1. Install the Slick RSS extension.
2. Add any RSS feed.
3. Add the Slick RSS tab to a tab group.
4. Left-click on any of the links from the feed.
5. A new tab is opened and it doesn't belong to any group.

Actual result:

A new tab that doesn't belong to a group.

Expected result:

A new tab that belongs to a group.

Reproduces how often:

Easily reproduced.

Brave version (brave://version info)

Brave	1.21.74 Chromium: 89.0.4389.72 (Official Build) (64-bit)
Revision	3f345f156bfd157bd1bea06310e55f3fb2490359-refs/branch-heads/4389@{#1393}
OS	Linux
JavaScript	V8 8.9.255.20
User Agent	Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.72 Safari/537.36
Command Line	/usr/lib/brave-bin/brave --user-data-dir=/tmp/tmp.388syXqXzz --enable-dom-distiller --disable-domain-reliability --no-pings --extension-content-verification=enforce_strict --extensions-install-verification=enforce --origin-trial-public-key=bYUKPJoPnCxeNvu72j4EmPuK7tr1PAC7SHh8ld9Mw3E=,fMS4mpO6buLQ/QMd+zJmxzty/VQ6B1EUZqoCU04zoRU= --sync-url=https://sync-v2.brave.com/v2 --lso-url=https://no-thanks.invalid --variations-server-url=https://variations.brave.com/seed --enable-features=WebUIDarkMode,PrefetchPrivacyChanges,PasswordImport,ReducedReferrerGranularity,AutoupgradeMixedContent,SafetyTip,LegacyTLSEnforced,DnsOverHttps --disable-features=TextFragmentAnchor,PrivacySettingsRedesign,SignedExchangeSubresourcePrefetch,IdleDetection,DirectSockets,AutofillEnableAccountWalletStorage,SignedExchangePrefetchCacheForNavigations,SubresourceWebBundles,AutofillServerCommunication,SafeBrowsingEnhancedProtectionMessageInInterstitials,TabHoverCards,NetworkTimeServiceQuerying,LangClientHintHeader,NotificationTriggers,WebOTP,SafeBrowsingEnhancedProtection --flag-switches-begin --flag-switches-end
Executable Path	/usr/lib/brave-bin/brave
Profile Path	/tmp/tmp.388syXqXzz/Default

Version/Channel Information:

• Can you reproduce this issue with the current release?
  Yes
• Can you reproduce this issue with the beta channel?
  Yes
• Can you reproduce this issue with the nightly channel?
  Yes

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields?
  N/A
• Does the issue resolve itself when disabling Brave Rewards?
  N/A
• Is the issue reproducible on the latest version of Chrome?
  Yes

Miscellaneous Information:

This is weirdly inconsistent. I see the same problem when clicking on the "Getting started" link in the "Edit This Cookie" extension options page, but not with links in the KeepassXC-Browser extension.