Refreshed thumbnail backup

[MxMaster3]

Firstly, great work on developing this software. Can the thumbnails be backed up as part of settings export? After a Windows reinstall or logging in from another PC, all the thumbnail images need to be downloaded again. For thousands of bookmarks this takes a while. Also, when the app is processing the thumbnail refresh, the focus shifts to the browser window of the bookmark being refreshed. This interferes with typing and working in other apps.

Thanks.