I figured out why the feature was failing on my system: I needed to enable Install and Run Studies under Send technical and interaction data to Mozilla under Firefox Data Collection and Use under Privacy & Security under Settings. I can understand why Mozilla would do that (they consider it an experimental feature).
Along the same line, the Firefox Labs section of Settings requires the same settings to be enabled. When I enabled it under about:config then opened the settings, the label would briefly appear then disappear. When I went back to about:config, I found the setting was reset to disabled. Again, I can understand why Mozilla would do that.
Yet understanding why is not the same as accepting why. If they want to promote themselves as an open and privacy preserving web browser, they should accept there are some compromises to be made when it comes down to letting users experiment and collecting telemetry.
Seems weird to announce it as part of a version and then also as a rolling release. Seems like the message could be much clearer by saying it is part of the browser but may be disabled by default.
FWIW, I checked about:config. There's some options in here that seem highly relevant
These are the settings I have by default that are not allowing grouping.
Changing `browser.tabs.groups.enabled` to `true` enables the feature. Though note that it can still be difficult to align them right such that they group. Presumably `browser.tabs.groups.smart.enabled` is the AI feature mentioned in the article. But I have no idea what `browser.tabs.groups.smart.optin` and `browser.tabs.groups.smart.userEnabled` are.
Yes, I updated. After doing so it told me about this feature. No, I also cannot see the tab group creation when right clicking. FF 138.0, Sequoia