cooloodoo The real mess here is that a Chrome browser has to be installed. Why is this a mess: beause it shows that Orion ability to use and install Firefox or Chrome extensions DOES NOT ACTUALLY WORK. Orion downloads the extension code; adds it to whatever metadata Orion maintains for extensions it has installed. It can run. But this necessary file for communication between the Bitwarden extension and the Bitwarden desktop file will not be present, as cooloodoo has proven.
The only viable workaround is to install a Chrome based browser first. Otherwise the needed file CANNOT be present.
It's ok to have bugs; it is divine to admit it; it is Divinity raised to a higher power (double entendre intended) to fix them (even if there is a goofy workaround--and it would help to correctly document said workaround as cooloodoo has done).
It is not that easy to get the extension working with Chrome and communicating with the desktop app. Install extension. Manage extension. Enable extension. Launch extension. Change setting to use biometrics in extension. Get prompted for password or finger to open running instance of extension. Yay, it works.
Then copy com.8bit.bitwarden.json to the folder noted above for Orion bitwarden application support. Go through the rigamorole to turn on biometric verification. On the third attempt the connection to the desktop Bitwarden occurs and the setting "sticks" in the extension.
Whether this is Bitwarden's fault or Orion's, it is a mess. One is inclined to say that it is Orion's fault because the process to enable biometric unlock for the extension works on Safari, Firefox or a Chromium based browser. The problem would seem to be as simple as Orion not installing the Chrome plugin correctly--so the process of accessing and installing "foreign" extensions--which is a great benefit (even it probably can't ever work for every extenstion, which is understandable)--still needs some work. The challenge will be that this work might be extension specific--I hope it is possible to do this w/o per extension work.
In any case, thanks to cooloodoo I have it working. For clarity I note that installing the Chrome Bitwarden extension from within Orion does NOT download the required file in the correct place--this is really the only actual problem.