Steps to reproduce:

1. Find item in content tree, that has subitems, that weren't already loaded into memory (that means, they weren't expanded)
2. In context menu, click "Select all"
3. expand item

Current behaviour:

Children aren't selected

Expected behaviour:

Children are selected Actually it's hard to tell, how exactly it should behave, as at the moment this whole "Select all" function is hard to comprehend - for example if you click "Select all" on specific branch and select option "Add to bookmarks" all these items (that aren't visible in tree) should be bookmarked, but at the moment it's impossible to achieve.