I am glad i could provide you a second glance. Yes, you've been wrong. It's basically Tor Browser without the Tor stuff - so based on Firefox ESR.
Wave
It is, just like Tor Browser, based on Firefox ESR.
Just do a Fingerprint Test:
coveryourtracks.eff.org
Is the other Browser better? No, you will have less privacy protection.
Yes, it is faster.
Mullvad Browser is Tor Browser without Tor. TorBrowser evolved over many years, with a very long track record and is recommended uncountable times all over the world. So, if you want the TorBrowser without all the Tor stuff: here is it.
You can still use a other web browser for other special usecases. Mullvad Browser has focus on privacy.
No. No other extension in Mullvad Browser. For other usecases besides of good privacy you should use a other browser.
Just do a Fingerprint Test:
coveryourtracks.eff.org
Is the other Browser better?
You will have less privacy due to fingerprinting and Mullvad-Browser has the advanced configurations that are in use for many years by TorProject. I never used LibreWolf but they described it as 'custom version of Firefox'. They integrated uBlockOrigin extension and if you add further extensions it will make you stand out.
It's all included. It's made for using it how it is - without installing AddOns. If you would need other addons you will just use another browser that offers that special usecase, but than with less privacy.
github.com/mullvad/mullvad-browser Firefox ESR - it's basically Tor Browser without Tor. Mullvad gets name recognition 100%
Yes, it's more anonymous than firefox with mods/addons. You can do "fingerprint" tests online to compare how unique your browser is. Just use the Mullvad Browser daily - and if you need something special - than you can still use a other solution for the special case.
Yeah the Mullvad-VPN recently stopped port-forwarding. But this Browser is not a VPN product. Just use it without VPN or use an other VPN provider, if you want.