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Have firefox quantum and firefox 47 in the same OS

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  • Last reply by James

Julio37
Julio37
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I use firefox 47 and i have all my extensions, and im satisfied i would like to use the new firefox quantum but i don't know if all my extensions will work my questions is.... i could installed quantum in my pc and not to lose firefox 47??? it means have 2 versions of firefox in my OS (operatic system) and you can guide me in the process or give me some link to make the process? Thank you

I use firefox 47 and i have all my extensions, and im satisfied i would like to use the new firefox quantum but i don't know if all my extensions will work my questions is.... i could installed quantum in my pc and not to lose firefox 47??? it means have 2 versions of firefox in my OS (operatic system) and you can guide me in the process or give me some link to make the process? Thank you

All Replies (2)

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
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Last year, I set up Firefox 52 (Extended Support Release) and Firefox 57 in separate program folders with different profiles so I could have access to one or two old add-on. However, I hardly ever use 52 except for testing and now it has passed its end-of-life.

The critical thing is separate profile folders. And keeping backups for the inevitable mess-ups that will occur.

More about profiles: Profiles - Where Firefox stores your bookmarks, passwords and other user data

Also, of course, you shouldn't use Firefox 47 on the web, where its security vulnerabilities were disclosed long ago and you can never be sure what kinds of attacks will launch from which sites because sites and ad networks can be unexpectedly compromised.

James
James
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Quantum refers to Firefox 57.0 and later.

Since you use Windows you could use the portable Firefox 52.9.0esr with the old legacy extensions you need to use. https://portableapps.com/apps/internet/firefox-portable-legacy-52

Portable Firefox will not touch your regular Firefox install or Profile. At least with 52.9.0esr you will also be much less vulnerable compared to the old 47.0.

Modified by James