Xy forgets tab locations?

[beethoven]

Since using the latest version 8.80.0300 it appears to me that XY sometimes forgets the location of my tabs. I am using both tabs and the catalogue (and love the flexibility) but when clicking the tabs I sometimes get the following errror message: "Location currently not available" and underneath the exact path of the file I want.

The point is that the file is available as I can click it on the tree or catalogue and it opens without problem. I also note that from time to time a file I open via the tree suddenly takes over a locked tab

[admin]

Thanks, but I've never seen this. Will keep an eye open...