small fraction of a line when clicking on a link on my web page and then return from that link
I have programmed a website (with partial use of Xara js code). On one page I have a link to impressum, data privacy etc. When I click one of the links and then return to previous page with "back", I get a small line at a position where no element is located. The line is connected with the last link selected as it changes color when hovering with the mouse over the button.
It seems that the effect appears only in Firefox and not in every installation, and neither in IE11 nor Edge nor Chrome. I have observed the same effect also on my mobile (Samsung S9). The line can be seen in the attached picture. For your developers I can also provide the link to that specific page if necessary.
This forum is focused on solving user problems with Firefox not on web development.
Please ask your web developer questions on stackoverflow and tag them firefox: https://stackoverflow.com/questions/tagged/firefox
You might also find this article on developer support helpful: https://support.mozilla.org/en-US/kb/where-go-developer-support