[peesem]

you have to go into your Privacy & Security settings and scroll down until you see something like "Posturr.app was blocked to protect your Mac." and then press "Open Anyway"

[altern8]

Ohhh... Thank you!

Is this new? In previous version I could just right-click and it would open it.

[tom_]

Looks like this changed for Sequoia: https://support.apple.com/en-gb/guide/mac-help/mh40616/15.0/...

And looks like Sonoma was the last version to support the right click menu: https://support.apple.com/en-gb/guide/mac-help/mh40616/14.0/...