Fluid is a somewhat old app, but can be rather useful. It containerizes any website, making it into an “app” that you can put in the dock and assign to a desktop – things you can’t exactly do with a browser window. iOS has an analogous builtin functionality where you can add a web page to your home screen, but Apple hasn’t done this for macOS (yet). I have a number of Fluid Apps I use on a daily basis and I find them very useful.

After updating to Sequoia however, I was rather irked that Apple’s new security settings did not afford me the opportunity to say, “Hey, I’ve been using these apps for years. I created them. I trust them. I trust the Fluid app developer. Just let me run them.”

When I first tried to launch my trusty self-created apps, I would be presented with 2 cryptic errors:

(“RT” by the way, is the ticketing system we use at work to track user requests. When I’m on “RT duty”, I switch to my RT desktop and start handling tickets. I have a self-rolled desktop-based time tracking system, so time I spend on that desktop goes toward my “RT Project”.)

I figured out a way around this irksome conundrum using code signing (which requires that you install xcode developer tools), but first, you have to remove what Apple now classifies as “detritus” with the following error if you try to code-sign an app that has things like resource forks:

$ codesign --force --deep -s - RT.app
RT.app: replacing existing signature
RT.app: resource fork, Finder information, or similar detritus not allowed

To remove the “detritus” and then code-sign an app (I’m using my RT.app), run the following in the Terminal.app:

$ xattr -cr RT.app
$ codesign --force --deep -s - RT.app

Be aware that `xattr -cr` removes all the app’s newly Apple-disallowed attributes, which may brick the app? In my case, it didn’t seem to break anything, but if you want to see what it will remove, to understand what will happen, you can list the attributes with `xattr -lr RT.app`.

From now on, you should be able to launch and use the app!