I found very strange bug, and it is easy to reproduce (on yours sample):
1. Open two tabs on browser with link https://docs.webix.com/samples/64_file_manager/04_loading/03_dynamic_loading_nocache.html#!//
2. Click for example on folder "newFolder" (on both tab)
3. Rename some inner folder in that folder (for example "newFolderInner1" to "newFolderInner12")
4. On that tab (where you rename), everything is correct. But, on second tab, when you load branch again (for example, click on parent root and then on folder "newFolder"), you will have "newFolderInner1" and also "newFolderInner2".
Setup that I use is loading with branch, noFileCache on true, and also I use "removeMissed" on true, but everything is same. Also, on rename files, everything is ok. I think that problem is because "loadBranch" don't clear folders.
If you have some quick solution, please write, but, I'm sure that you will correct this bug on next version