[FIX] website: Edition with Firefox with CSS of external domains.
[FIX] website: Edition with Firefox with CSS of external domains.

Firefox doesn't allow to access sheets cssRules
In such a case, we just pass, these css rules will simply
not be available for the edition of some inputs.

Probably, when a real use case needing these external css rules
will come, we will probably need to fetch these style sheets
another way.

opw-642752

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