If you click "choose default apps by protocol" do you see Firefox as an option under the http and https protocols?

The option "set defaults by app" on the Default apps settings page is what you want.

No. It is not available to select when choosing by protocol nor is it listed in the apps list on set defaults by app.

I just looked at my desktop (Firefox 72.02) and it appears everywhere and is available to select everywhere it should be. As I was writing this Firefox updated to 73.0 on the desktop and after I restarted it, everything still works there. I was sort of thinking it could be something to do with Firefox 73 but evidently it's something on the laptop.

I was also thinking it had to do with group policies. I've never (knowingly) set a group policy on either machine but every once in awhile Windows will tell me I can't change something because that thing is being controlled by a group policy. I looked at the group policy control panel earlier this morning but didn't see anything that I recognized as a restriction on the browser. I might try setting a restore point then resetting all of them to factory settings and see if that makes a difference.

If all else fails and you decide to re-install, consider installing the 32-bit version. Some users have reported issues with the 64-bit and this method was successful at resolving them.

Chris Schleter said

nor is it listed in the apps list on set defaults by app.

Hello Chris,

Probably a redundant remark, but in Windows Settings => Default-apps, under "Webbrowser": if another browser is listed there; when you click on it you should get a dialog where you can choose Firefox.

You don't get that option ?

Robertj - I ended up going with the 32-bit version which doesn't make me particularly happy but at least it works.

McCoy - the issue was that Firefox did not appear in any selection list in Default Apps.

Chris, would you be so kind as to mark RobertJ's post as
Chosen Solution ? It's the "Solved the problem" button to the right of his post.

Thank you in advance !

Chris Schleter said

Did Microsoft do something that prevents Firefox from being the default browser? Is there another mechanism I can use to make Firefox the default?

I remember hearing that there was a patch for IE11 and it took three more patches to get the patch to work. Ultimately, some user's reported that IE11 was "stuck" as their default browser. I have IE11 turned off in Windows features so, I can't confirm this. Just a thought.

Chris Schleter said

No. It is not available to select when choosing by protocol nor is it listed in the apps list on set defaults by app. I just looked at my desktop (Firefox 72.02) and it appears everywhere and is available to select everywhere it should be. As I was writing this Firefox updated to 73.0 on the desktop and after I restarted it, everything still works there. I was sort of thinking it could be something to do with Firefox 73 but evidently it's something on the laptop. I was also thinking it had to do with group policies. I've never (knowingly) set a group policy on either machine but every once in awhile Windows will tell me I can't change something because that thing is being controlled by a group policy. I looked at the group policy control panel earlier this morning but didn't see anything that I recognized as a restriction on the browser. I might try setting a restore point then resetting all of them to factory settings and see if that makes a difference.

Hi Chris

I seem to have the same problem: Can't find Firefox as App to set as default browser. What do you mean with 73 and 72.02 and what do you mean with 32-bit instead of 64-bit version.

Can you help me to solve the problem too?

I was referring to Firefox versions 73 and 72.02. I have a 64-bit computer and was using the 64-bit version of Firefox. When I changed to the 32-bit version, I could select Firefox as the default. Not sure if what I was seeing is an issue with 64-bit Firefox or with Windows 10 (v1909). Hope this helps.thoscherrer said

Chris Schleter said

No. It is not available to select when choosing by protocol nor is it listed in the apps list on set defaults by app. I just looked at my desktop (Firefox 72.02) and it appears everywhere and is available to select everywhere it should be. As I was writing this Firefox updated to 73.0 on the desktop and after I restarted it, everything still works there. I was sort of thinking it could be something to do with Firefox 73 but evidently it's something on the laptop. I was also thinking it had to do with group policies. I've never (knowingly) set a group policy on either machine but every once in awhile Windows will tell me I can't change something because that thing is being controlled by a group policy. I looked at the group policy control panel earlier this morning but didn't see anything that I recognized as a restriction on the browser. I might try setting a restore point then resetting all of them to factory settings and see if that makes a difference.

Hi Chris

I seem to have the same problem: Can't find Firefox as App to set as default browser. What do you mean with 73 and 72.02 and what do you mean with 32-bit instead of 64-bit version.

Can you help me to solve the problem too?

I was referring to Firefox versions 73 and 72.02. I have a 64-bit computer and was using the 64-bit version of Firefox. When I changed to the 32-bit version I could select Firefox as the default. Not sure if the problem is with Firefox 64-bit or Windows 10 (v1909). Hope this helps.

I seem to have the same problem: Can't find Firefox as App to set as default browser. There are 3 choices in Windows 10 settings to chose a default Web Browser: Microsoft Edge, Internet Explorer or look for an app in Microsoft store. There is no button to choose any other browser. How can I make Firefox my default browser? ? ? ? ? ? ? I have Firefox ver 73.0.1 64 bit. Someone at Firefox needs to talk to someone at Microsoft and find a solution to this problem. Feb 29 2020