This add-on does two things: turn on "Request Desktop Site" by default and disable the 980 pixels viewport. On a 160 dpi tablet, the resultant web page will be exactly like using the desktop version of Firefox. No more blurry lines.
If you think this add-on violates Mozilla's add-on policies or has security or privacy issues, please report these issues to Mozilla using this form.
Please don't use this form to report bugs or request add-on features; this report will be sent to Mozilla and not to the add-on developer.