Hello @CrushaKRool,
Welcome back to the Sonar Community!
Thank you for your feedback. It appears that the rule property description lacks information on using regular expressions. The provided regular expression should adhere to JavaScript syntax for regular expression literals (/pattern/).
Please try adding the slash character (/) at the beginning and end of your regex as follows:
/Material (Icons|Symbols)\s?(Outlined|Round|Sharp|Two Tone)?/
Let me know if the suggested fix works for you. If so, I will create a ticket to improve the description of the rule property.
Cheers,
Yassin