Makes more clear the is_enable function in themes

[mattiagiupponi]

Checklist

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[codecov]

Codecov Report

Merging #11631 (2bf2199) into master (da856b5) will increase coverage by 0.00%.
The diff coverage is 100.00%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #11631   +/-   ##
=======================================
  Coverage   62.46%   62.46%           
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  Files         873      874    +1     
  Lines       52034    52038    +4     
  Branches     6497     6497           
=======================================
+ Hits        32502    32506    +4     
  Misses      17977    17977           
  Partials     1555     1555