ScanListener hides error messages on scan start
The ScanListener hides potential error messages on scan start e.g. if the output hdf5 file is opened by external application like silx view
we display the following message in the bliss application:
!!! === ValueError: Unable to create group (no write intent on file) === !!! ( for more details type cmd 'last_error' )
however, when the ScanListener pops up, it is never shown until F5 is pressed and it is not obvious to the user that there is a problem