[Backport] fix: don't revert to advanced editor if block contains copied_from fields (#2661)

[navinkarkera]

(cherry picked from commit 2215fc5)

Backport of #2661 (comment)

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Codecov Report

✅ All modified and coverable lines are covered by tests.
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Additional details and impacted files

@@               Coverage Diff               @@
##             release/ulmo    #2695   +/-   ##
===============================================
  Coverage                ?   94.80%           
===============================================
  Files                   ?     1226           
  Lines                   ?    27526           
  Branches                ?     6042           
===============================================
  Hits                    ?    26095           
  Misses                  ?     1373           
  Partials                ?       58           

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[ChrisChV]

Looks good 👍

• I tested this: I verified that the bugs are gone in Ulmo
• I read through the code and considered the security, stability and performance implications of the changes.
• I tested that the UI can be used with a keyboard only (tab order, keyboard controls).