When opening .html / .url files or running FirefoxPortable.exe again I now get:
Close Firefox | Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window.
My FirefoxPortable.ini reads:
[FirefoxPortable]
FirefoxDirectory=App\firefox64
ProfileDirectory=Data\profile
SettingsDirectory=Data\settings
PluginsDirectory=Data\plugins
FirefoxExecutable=firefox.exe
AdditionalParameters=
LocalHomepage=
DisableSplashScreen=true
AllowMultipleInstances=true
DisableIntelligentStart=false
SkipCompregFix=true
RunLocally=false
Visit the Community page
Join our forums
Subscribe to our email newsletter
Subscribe with RSS
Follow us on BlueSky
Follow us on Facebook
Follow us on LinkedIn
Follow us on Mastodon
Follow us on Twitter
AllowMultipleInstances only allows you to run two separate instances of Firefox with different profiles. It will break the ability to pass in URLs or HTML files or start Firefox again other than those two instances. This is the way Firefox works when used with -no-remote.
Sometimes, the impossible can become possible, if you're awesome!
I set AllowMultipleInstances to true so I can open portable Firefox ESR to use Scrapbook X addon to edit a web page I was reading in portable Firefox Quantum.
But if "Multiple Instances Breaks URL/HTML passing" then I can either use Quantum and ESR versions at the same time, or only Quantum with the ability to pass HTML files (as a new tab).
Can you still not open the files in question in your instance of Firefox if you drag and drop them to it? I used to do that, and it worked fine.
Can do that.
What I really need is a simple app to edit web pages and save as an .mht file, like Scrapbook X and UnMHT addons do (delete DOM elements, text editing and highlighting).
I mainly use Scrapbook X to clean web pages before saving as an MHT file to reduce the size and keep it as one file.
The other app I need is something like Stylizer to remove unused CSS elements to also reduce the size.
EDIT: When portable Firefox ESR is running (sandboxed, btw) and I try to open a .mht file portable Firefox opens, but still get message about closing Firefox. If I click Cancel portable Firefox remains, but with empty tab. If I click Close there's a loop with portable Firefox closing and opening (plus additional session restore tab).