Thanks for reaching out to us here in the Community. I'm here to help fix the issue you're having with the inactive taxes.
Are you referring to an inactivated Sales Tax agency in QuickBooks Online (QBO)? If so, once a sales tax has been inactivated, it would be automatically removed from the tax list. To verify if the issue has something to do with your browser, try logging into your QBO account through the Private browser mode.
Here are the different keyboard shortcuts to open a private browser: