Middle button doesn't invert selction any more

using the mouse button on tool bar to invert file selection has stopped working, left button select all and right button de-select all both work.
middle mouse button invert selection doesn't but hot key ctrl + I works, in the key editor it has Select INVERT as the command and ctrl + I as its hot key.
Is there any reason its stopped working on the toolbar button but hot key still working ?

Does the middle mouse button work elsewhere? E.g. can you toggle a file selection by middle-clicking?

not in directory opus, I never noticed it doing in anything else its been that long I've been using this.

That may mean the mouse drivers are configured to map the middle button to something else.

This is about Logitech, but several other drivers are similar as well:

mines a Corsair Dark Core RGB Pro SE and it worked fine until last week or the week before.

Corsair's drivers have a similar option.

couldn't get that working either.
been testing and it seem my middle mouse button now needs a long hard push down to register it working, but switch cleaner to the rescue, a good spray and lots of pushing has freed it up and its now working again.
sorry to have bothered you over something I should have tried first.