I want a custom button that is only enabled when audio track files encoded with MP3, AAC, or FLAC are selected, so I added the following modifier to my button with the Command Editor:
@disablenosel:type=*.(mp3|m4a|flac)
It works most of the time, but the problem is that when I am in a Lister in dual-display mode and one of these audio files is selected in one of the displays, and then I click on an empty area in the other display, sometimes the button remains enabled with no files selected at all.
This happens when the button is placed on a new toolbar I created. However, If I move it to one of the default toolbars, then it works as intended.
It sounds like something which was fixed (for slightly different reasons) recently, possibly only in the beta releases so far.
(It won't be the default vs custom toolbars exactly, but which commands are also on the toolbars. I think if any button runs the Set command then the toolbar updates more often than if no buttons use that command. The standard toolbars tend to have at least one such command, so they get updated a lot. The recent change makes the updates happen more often even without any Set commands on the toolbar.)