No problems here, I get the same layout as in the second screenshot. You may have accidentally zoomed webpage(s). Reset the page zoom on pages that cause problems. *<b>View -> Zoom -> Reset</b> (Ctrl+0/Command+0 (zero)) *https://support.mozilla.org/en-US/kb/font-size-and-zoom-increase-size-of-web-pages If you have made changes to Advanced font-size settings like increasing the minimum/default font-size, try the Default font-size setting "16" and the Minimum font-size setting "none" to see if that makes a difference. *Settings -> General -> Language and Appearance -> Fonts -> Advanced -> Minimum Font Size (none) Make sure you allow pages to choose their own fonts. *Settings -> General -> Language and Appearance -> Fonts -> Advanced<br>[X] "Allow pages to choose their own fonts, instead of your selections above" It is better not to increase the minimum font-size, but to use the built-in Firefox Zoom feature. *Settings -> General -> Language and Appearance -> Zoom ---- You can try these steps in case of issues with webpages: You can reload webpage(s) and bypass the cache to refresh possibly outdated or corrupted files. *hold down the Shift key and left-click the Reload button *press "Ctrl + F5" or press "Ctrl + Shift + R" (Windows,Linux) *press "Command + Shift + R" (Mac) Clear the Cache and remove the Cookies for websites that cause problems via the "3-bar" Firefox menu button (Settings). "Remove the Cookies" for websites that cause problems: *Settings -> Privacy & Security<br>Cookies and Site Data: "Manage Data" "Clear the Cache": *Settings -> Privacy & Security<br>Cookies and Site Data -> Clear Data -> [X] Cached Web Content -> Clear *https://support.mozilla.org/en-US/kb/clear-cookies-and-site-data-firefox *https://support.mozilla.org/en-US/kb/how-clear-firefox-cache Start Firefox in <b>Troubleshoot Mode</b> to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if <b>hardware acceleration</b> or if <b>userChrome.css/userContent.css</b> is causing the problem. *switch to the Default System theme: "3-bar" menu button or Tools -> Add-ons -> Themes *do NOT click the "Refresh Firefox" button on the Troubleshoot Mode start window *https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode *https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems *https://support.mozilla.org/en-US/kb/enhanced-tracking-protection-firefox-desktop *https://support.mozilla.org/en-US/kb/smartblock-enhanced-tracking-protection *https://support.mozilla.org/en-US/kb/trackers-and-scripts-firefox-blocks-enhanced-track