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[darkdh]

fix #10122

Auditors: @bsclifton

Test Plan:
See #10122

Submitter Checklist:

• Submitted a ticket for my issue if one did not already exist.
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).
• Ran git rebase -i to squash commits (if needed).
• Tagged reviewers and labelled the pull request as needed.

Reviewer Checklist:

Tests

• Adequate test coverage exists to prevent regressions
• Tests should be independent and work correctly when run individually or as a suite ref
• New files have MPL2 license header

[codecov-io]

Codecov Report

Merging #10124 into master will decrease coverage by 0.01%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master   #10124      +/-   ##
==========================================
- Coverage   52.69%   52.67%   -0.02%     
==========================================
  Files         227      227              
  Lines       20174    20179       +5     
  Branches     3230     3231       +1     
==========================================
  Hits        10630    10630              
- Misses       9544     9549       +5

Flag	Coverage Δ
#unittest	52.67% <0%> (-0.02%)	⬇️

Impacted Files	Coverage Δ
app/browser/windows.js	17.24% <0%> (-0.34%)	⬇️

[diracdeltas]

should this go in 0.18.x hotfix? otherwise users with pinned tabs will lose them again when the hotfix comes out

[bsclifton]

Good call @diracdeltas; I updated this PR and issue to be 0.18 hotfix 😄

[bsclifton]

LGTM 😄