fix header cloning bug

[tsctx]

Refs: #3160 (comment)
Refs: #3161

[KhafraDev]

LGTM with green ci, this is what I was thinking

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.13%. Comparing base (034e3f0) to head (9493e11).
⚠️ Report is 970 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##           main    #3162       +/-   ##
=========================================
+ Coverage      0   94.13%   +94.13%     
=========================================
  Files         0       90       +90     
  Lines         0    24334    +24334     
=========================================
+ Hits          0    22908    +22908     
- Misses        0     1426     +1426     

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