Last good version of Firefox, i.e. the version before Firefox forces WebExtensions thus completing the transformation into shittier-Chrome:

Firefox 56

Firefox 57 as the first release where only WebExtensions will be supported | Hacker News
https://news.ycombinator.com/item?id=13675097

Also… Stupid Web Design

https://portableapps.com/apps/internet

No link to ESR version of Firefox. SMH.

Proper link:

https://portableapps.com/apps/internet/firefox-portable-esr

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