Thank you for the review.

Please see if version 3.0.21 (available from August 31, 2020) addresses the zoom settings to your satisfaction.

There may be a slight difference in the font size of zoomed pages (compared to the extension customized font size) due to rounding -- I scale the font size based on the zoom percentage rather than reset the zoom to 1 before applying the extension specified font size. This is not the ideal fix -- which requires an enhancement to the webextensions api (functionality not supported at this time).