All of a sudden, after waking my computer from sleep, I found that many websites in Firefox are displaying the main text content at 13px, ignoring font sizes specified in… (read more)
All of a sudden, after waking my computer from sleep, I found that many websites in Firefox are displaying the main text content at 13px, ignoring font sizes specified in CSS etc. I first discovered this on my organization's website, I thought it was a browser cache issue, but it has persisted. The text content on our front page is all the correct size, but everything on the website that is "main content" text that is not in a heading tag, like blog post or regular page content, is rendered at 13px. Other sites like Wikipedia load this way as well. In private mode, the issue disappears. In Chrome, the issue does not occur.
I have cleared all cookies, browser cache, site data, history, and the problem persists. I have checked the default font settings in Firefox, the checkbox saying websites should override the font settings is already checked. Zoom is set to 100%. I updated to the latest version in the course of restarting, and it didn't fix the issue either.
In the attached screenshot, the examples on the left are in regular Firefox windows. On the top right, a page on our site is displayed correctly in Firefox private mode. In the bottom right, Wikipedia is displayed correctly in Google Chrome.