Inserts are highlighted but there aren't any

I opened an older project and it shows yellow i's in the mixer, indicating active inserts, if I understand it correctly. But there are no actual inserts showing. So my guess is that these are VST plugins that are no longer installed (or named differently) on this system, but I don't see a way to find out what they were.
There's no pop-up or warning saying that effect X can no longer be found, the way off-line media is.

Am I overlooking anything or should I put this on the feature request list?

I can't answer to this specific problem, but I like the idea of improving the error handling when plug-ins are no longer available, much like my own FR for missing fonts. (Below)

viewtopic.php?f=33&t=100236

Projects containing VST plugins that are not installed on the system are still indicated on the Buss or Track insert - the insert and the individual plugin instance may be bypassed.

The plugin's UI may not be opened as the "Controls" icon for that instance is bypassed and the Inspector does not expose the plugin's controls.

The exception is Audio Unit plugins on macOS which indicate generic Apple Audio Unit instances if the plugin is not installed or available on the system.

In the Fairlight Mixer's Additional Options (3 dots) menu is the Effects option enabled?
Note that the Insert icon is always visible but the Effects block on the Mixer UI may be hidden.

Select the Track or Buss and open the Inspector. Is the VST plugin listed in the Effects tab?

Reynaud, thank you for the suggestion.
The Effects Option in the 3-dot menu was enabled. The insert button is yellow, but there's no 'missing effect' list. I took a look at the Resolve logs, but opening a project without the necessary plug-ins does not result in an entry in the log unfortunately, so troubleshooting is a no go.

Are any VST plugins listed in the Inspector's Effects tab when selecting a Track or Buss with an active Insert button?

A Project file without media may also be useful in reproducing the issue.

Are any VST plugins listed in the Inspector's Effects tab when selecting a Track or Buss with an active Insert button?

A Project file without media may also be useful in reproducing the issue.

No there aren't. There's just the indication of something that's no longer there.

There's just the indication of something that's no longer there.

If a plugin has been instantiated but is no longer available (or installed), the Inspector indicates this to the user.

If an editor does not have access to the plugins instantiated within the current Project or Timeline they may continue unimpeded, save the Project and hand the Project back over to the editor with the required plugins without penalty.

Missing Plugin Inspector.png (25.29 KiB) Viewed 630 times

Reynaud, thanks for sticking with me. I'm on Windows, are you as well?

This is how the mixer looks for me. The little 'i' is yellow, but there's nothing there in the 'effects' section.
That wouldn't be possible either since one of the missing plug-ins was put on the 'master' slider of the audio, so there wouldn't be anything to show in the inspector, since there is no direct connection to the clip.

Empty_inserts.jpg (16.65 KiB) Viewed 622 times

So there's no error message like you have in your screenshot. And as soon as I click the yellow 'i' it becomes deselected and I can't reselect it either. (which makes sense since there's nothing to activate)

On macOS in version 17 the Inspector indicates missing or unavailable plugins in both Fixed or Flexi Bus modes if present in the Project.

A Project file without media may be useful - Private Message a link if you do not wish to attach directly in this thread.