Using + button to save new sharing links is not obvious
In Arvados 2.6.3, the expected flow for the sharing dialog is, you use the entry box to find people and/or group(s) to share with, then press the + button to create the links. The second step is easy to miss. We should improve the usability of this.
Right now you're always expected to select a person and/or group from the pulldown for disambiguation. I think the ideal solution would be to create the sharing link as soon as a selection is made from that pulldown. The + button could be replaced with a second pulldown that lets you choose a read/write/manage permission level for newly added links.
If that's difficult or creates its own problems, another would be to have a confirmation dialog if the user dismisses the sharing dialog while there are selections in the new link entry area. The dialog could offer them the option of creating those links or not. If the user hasn't had a chance to specify a permission level yet, this dialog could prompt for that too.
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