Other websites (like Slashdot and Core77) load computer-destroying scripts (often as part of an anti-adblock strategy). For these, I use "Javascript Toggle On and Off," which lets you create a blacklist of websites that aren't allowed to run any scripts:
addons.mozilla.org/en-US/firefo...
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addons.mozilla.org
JavaScript Toggle On and Off (WebExtension) – Get this Extension for 🦊 Firefox (en-US)
Download JavaScript Toggle On and Off (WebExtension) for Firefox. Toggle JavaScript engine on and off the easy way