Hello,
Thank you for posting in Microsoft Q&A.
Based on the description, I understand your question is related to OperaGXsetup virus.
You can use windows defender to do a full scan.
Open windows security, click Virus & threat protection, choose Scan options as full scan and wait for the process to finish.
Also, it seems you are using Firefox currently, but as a Microsoft forum, it mostly provide information with Microsoft products and services.
Since there are no engineers dedicated to Firefox and OperaGXsetup in this forum. in order to be able to get a quick and effective handling of your issue, I recommend that you repost your question to related website.
Have a nice day.
Best Regards,
Molly
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