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Will installing Firefox Developer Edition interfere with my Firefox installation???

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Greetings everyone,

Firefox is my preferred browser and I really prefer the Firefox Engine over Chromium that most other browsers use.

I want to install a backup browser that runs the Firefox Engine in case my Firefox browser has a problem.

I searched a lot and I thought installing this would be the best option: https://www.mozilla.org/en-US/firefox/developer/

However, I’m worried that installing the Firefox developer edition will change my Firefox installation…

( :( :(
Greetings everyone, Firefox is my preferred browser and I really prefer the Firefox Engine over Chromium that most other browsers use. I want to install a backup browser that runs the Firefox Engine in case my Firefox browser has a problem. I searched a lot and I thought installing this would be the best option: https://www.mozilla.org/en-US/firefox/developer/ However, I’m worried that installing the Firefox developer edition will change my Firefox installation… :( :( :(

All Replies (12)

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Dropa said

Here's more info on that Developer verison and FAQ: https://support.mozilla.org/en-US/questions/1336530 Developer is a beta version. If your having issue you should stay with current til a release public is out. Beta is only for testing and some features stay and some stay only as beta. You shouldn't use both but if you do you need to do when installing it - you should install in it's own separate folder so if you uninstall it doesn't interfere with the regular Firefox install.

Thank you for your response Dropa!

If I installed another Firefox based browser, how can I prevent it from changing my main Firefox browser?

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Dropa said

Look at these: https://support.mozilla.org/en-US/kb/make-firefox-your-default-browser#:~:text=Go%20to%20the%20Windows%20Start,a%20list%20of%20available%20browsers. https://blog.mozilla.org/en/products/firefox/how-to-set-firefox-as-your-default-browser-on-windows/ And when you finish install it usually ask if you want to make that install browser default at that point you can uncheck or cancel that option. Otherwise the two links posted are about how to set a Default browser.

Thank you for your response!

Sorry I wasn't clear with what I meant about installing another web browser that's based on the Firefox Engine. I meant this:

Is it possible that after installing another separate web browser like Waterfox that it'll change the settings in my Firefox install?

I didn't think this was possible but I just read that this can happen... :( :( :(

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Dropa said

You can install Firefox 107 and 104 as long as you create separate folder for each install so they don't over-write the install folder. And it should create two separate Desktop icons for each though you might have to label one Firefox 107 and the other Firefox 104 so you don't click the wrong one. Just remember you have to install in separate folder in the program/files or program/files/x86 folder. If you don't do this it will over-write older and if it detects newer will ask if you want to install in that folder. So you can install Nightly and Firefox with separate folder so they have their own .exe files when run them. That's my experience wise. What you want should try is install and get it start to where it ask where do you want to install and that where you can change the folder location other then default folder setup. Just remember .exe files folder must be on C:\ drive you can't move it from there for the most part. I could be jumbling things here but if done right you can have more then one version of Firefox engine or Browser with their own separate install folder and icons that will functions like the other but have their own saved data profiles connect to that Browser version.

Thank you for your response!

I'm too nervous that if I install another Firefox.exe(even if it's a nightly build and in a separate folder) that they'll get mixed up and I'll lose my Firefox session that contains my opened tabs and windows.

What about Waterfox? Could that interfere with my Firefox.exe??? :'( :'( :'(

I've used PaleMoon a little bit and I haven't had a problem with that as yet.
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Firefox Developer Edition, unlike most other releases, DOES install into its own folder and DOES create its own separate profile folder (i.e., it won't pick up any settings from disk -- you could share settings using Sync if you wanted). In my opinion, Developer Edition is the best choice for a second Firefox, assuming you don't mind a bit more instability as new features are finalized.

Regarding your session data, you can back up Firefox's current session history files if you like. I'll give you the location below the line.

You also can use add-ons to back up your current session. I haven't tested any of these in the past couple years, but I think these are still the main ones:


Session History File Backup

(1) You can open your current Firefox settings (AKA Firefox profile) folder using either

  • "3-bar" menu button > Help > More Troubleshooting Information
  • (menu bar) Help > More Troubleshooting Information
  • type or paste about:support in the address bar and press Enter

In the first table on the page, find the Profile Folder row and click the "Open Folder" button. This should launch Windows' File Explorer listing the contents of your current profile folder.

(2) In your profile folder, double-click into the sessionstore-backups folder.

(3) Copy all files here and paste in a safe location such as a new subfolder in your Documents folder like "Session2022-12-03" or similar.

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Regarding Waterfox, we occasionally have Waterfox users post about a problem here, but you would be better off asking on their forums.

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Note that the Developer Edition updates twice per week just like the Beta version. You can also consider to use an extra Firefox profile (possibly with no extensions installed) with release that you can use in case of issues with your main profile.

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There is also the ESR version (currently 102.5.0) aimed at organizations that only receives security and stability updates.

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Wow, thanks for all your responses! They're very helpful!

I get incredibly anxious because I depend on Firefox for so many things and if it stopped working then I'd be in a lot of trouble... :'( :'( :'(

It's SUPER important for me to have a backup for Firefox in case something goes wrong and I'm unable to use it.

I'm still doing research from the links posted, but it seems like https://www.mozilla.org/en-GB/firefox/developer/ is the best "Firefox backup"?

I'm just worried that when I install this Developer Edition I'll be at risk of losing my settings and my opened tabs in my current Firefox install... :'( :'(


EDIT: My main concern is keeping the Firefox backup App separate from the primary Firefox App I'm using right now for everything I do. I don't want any risk of the Firefox backup App to alter the primary Firefox App in any way.

Helpless_Quest modificouno o

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I've been researching Firefox Developer Edition and it seems good, but I'm extremely afraid of using it becauase it says that it sends user data back to Mozilla and it doesn't look like this feature can be turned off... :(

Is there another option?

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You can manage telemetry data in the Settings on Firefox Developer Edition in the same manner as regular Firefox: Telemetry collection and deletion.

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jscher2000 - Support Volunteer said

You can manage telemetry data in the Settings on Firefox Developer Edition in the same manner as regular Firefox: Telemetry collection and deletion.

Thank you for your response!

By following your steps, will I be able to remove and stop ALL of the telemetry and ALL of the data that is sent to Mozilla?

I was looking at Firefox portable, but this isn't made by Mozilla so I want to stay away from it.

Are there any other options I can look at? :( :( :(

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Helpless_Quest said

By following your steps, will I be able to remove and stop ALL of the telemetry and ALL of the data that is sent to Mozilla?

I really can't vouch for ALL, but you will note that none of the technical information would be personal information anyway. Please review the support articles.