Light theme glitches tab groups

[iam-cult]

Description

The standard light theme causes visual glitches with tab groups.

Steps to Reproduce

1. Enable the light theme
2. Create a tab group
3. Observe visual glitch

Actual result:

The line on the current tab is wider than the line below the tab.

Expected result:

Both lines are the same length

Reproduces how often:

Easy

Brave version (brave://version info)

Brave	1.32.115 Chromium: 96.0.4664.93 (Official Build) unknown (64-bit)
Revision	17531e0a70b4f8108f2418e8b5117f465077710b-refs/branch-heads/4664@{#1229}
OS	Linux

Version/Channel Information:

• Can you reproduce this issue with the current release?
  Yes
• Can you reproduce this issue with the beta channel?
  I cannot install this channel
• Can you reproduce this issue with the nightly channel?
  I cannot install this channel

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?
  No

Miscellaneous Information:

Brave installed from flathub beta

[jdsimcoe]

I've reproduced this same visual bug in macOS fwiw:

Light mode

Dark mode

[iam-cult]

also happens on multiple third party themes

[jdsimcoe]

@iam-cult is there a timeline for them fixing this?