You need to provide the problem link along with the screenshot so others can verify if they have the same issue in their Firefox as well. And if it worked fine in Trouble shooting mode that would mean you got Addon or Extension issues happening here. Firefox has no control how short url or dashlane works that's beyond Firefox control.

I disabled all add-ons, and it made no difference.

Here's one of the pages I am having the issue with, just scroll through the page. https://therecipecritic.com/baked-rigatoni/

I tried that link on Firefox for Windows 10 and not scrambling scrolling up or down. Are you sure your resolution is set correctly?

I am on a 27" iMac, and it has one resolution; 5120 x 2880. Since this does not happen on every web page I go to, and I have checked the pages with Safari (no scrambled characters) I tend to think it's a Mozilla issue.

You can check in Font Book for font issues like corrupted and duplicate fonts.

This can be caused by a problem with fonts you have installed locally and that might be corrupted or are missing variants. You will have to identify and remove corrupted font(s).

You can right-click and select "Inspect" to open the built-in Inspector with this element selected.

• https://firefox-source-docs.mozilla.org/devtools-user/page_inspector/how_to/open_the_inspector/

You can check in the Rules tab in the right panel in the Inspector what font-family is used for selected text. You can check in the Fonts tab in the right panel in the Inspector what font is actually used because Firefox might be using a different font than specified by the website.

• https://firefox-source-docs.mozilla.org/devtools-user/page_inspector/how_to/edit_fonts/

Note that you shouldn't disable "Allow pages to choose their own fonts, instead of your selections above" as this will cause issues with iconic fonts used by webpages to display small icons (you may see text labels instead of icons).

Thank you for the detailed help. I found that Helvetica Neue was corrupt, and I was able to replace it.