Firefox Portable

Windows x64, Firefox 78.15, copied on local system disk
I have quite strange situation: when I run Firefox from shortcut, it uses profile from ...\FirefoxPortableESR\Data\profile as expected, but when I press a link from email, it switches to %APPDATA%\Roaming\Mozilla\Firefox\profile which is definitely not what I want. Moreover, I see all that bunch of mozilla folders in %PROGRAMDATA%, %APPDATA%\Local, %APPDATA%\LocalLow and %APPDATA%\Roaming. So what's wrong with me/Mozilla/outer space etc.?

FireFox portable still writes data in %ProgramData%\Mozilla relating to the updater...

So I've noticed the firefox account keeps getting disconnected every few hours and I have no clue why. I use the account because of its password manager sync capability. Any ideas why this happens?

I have two laptops.

Acer Aspire 5, which is really old.

Acer Nitro, which is an entry level gaming laptop.

If you remember, many months ago, I was having some issues with Firefox Portable. I forgot what they were. But I did a clean install and started over and did everything right that time. So there shouldn't be any issues.

So anyway, I've been getting a lot of update alerts from the browsers on both computers and have been constantly launching PortableApps.com Platform to update the browser.

I happened across this in another forum.
https://ffprofile.com/

Maybe it'll be of some use to someone.

First post, newbie.
I have Firefox ESR 52 installed on my desktop (for old school reasons, eg Classic Theme Restorer), and would like to try latest Firefox Portable ESR. I would install it to the same 8 GB flashdrive that has my mail client: Thunderbird Portable Legacy 3.1 (great little program, clean functional interface, never any issues). There's over 7 GB of free space on this flashdrive.
Couple of concerns:
Any way to set Firefox Portable to be the default browser which launches when I click on a link in an email in Thunderbird Portable?

Like the title says. I only use Tabliss, Dark Reader and uBlock Origin. These never gave me problems until recently when I updated Firefox Portable to 92.0.1 or somesuch, and, updating to 93 after that didn't make the problem go away. If I close Firefox Portable and open again right away, the addons load normally. The issue could be related to Sandboxie-Plus, as it always occurs after I emptied the sandbox, but it also happens sometimes (sometimes frequently) if I run Firefox Portable unsandboxed.

With the AllowMultipleInstances=true in FirefoxPortable.ini (that's in my C:\FirefoxPortable folder along with the FirefoxPortable.exe file) when I try to open a 2nd instance it gives the same error popup dialog again that I also got a few months ago when I was still on a (slightly) earlier version of Firefox Portable, and that used to be fixed in an updated version until it came back as of 93.0.

firefox extension DownThemAll has been back in action for a while now

so it ( https://portableapps.com/apps/internet/downthemall_extension ) should be listed again as available in the list of https://portableapps.com/apps

I originally posted on Mozilla's help site, they referred me to here:

I'm using Firefox Portable. For some reason, in text fields, firefox will randomly "paste" (for lack of a better term) the localhost into a text field and act like it's pressed enter. It first started when I was typing, but now it can occur when I'm changing tabs and occasionally when I'm doing nothing at all. No other programs on these systems are doing this.