Icon bar & snapshots

[ngeezer]

Host: Kubuntu 17.04
Guest: Windows 10 and windows 8.1
VBox version: 5-1-28

Have 2 unrelated questions.

1: I used to have an icon bar across the top of the window with icons for "file,machine,view,input,devices,help". In exploring recently I managed to delete the bar. I know I can use "Right-Ctrl,Home" to bring up a window with the list of options. But I keep forgetting the key combination to do so and have to spend time reading the manual to retrieve the key combination. I have been reading the manual to try and restore the icon bar. I read that using the CLI interface I can use "VBoxManage setextradata" to reset the icon bar to default (at least I think that what the words meant). But when I try the command, it has no effect.

So How do I get the icon bar back?

2: snapshots. What is a good guide/discussion in when to create snapshots. I have been doing it before I install some new s/w to try with the thought that I can always revert to the previous snapshot if the s/w isn't working or messes things up. Also whenever Windows is asking to do a major update. But Windows changes things without asking sometimes (always?) and I haven't made a snapshot previous to the update. Anyway I don't want to fill the hard disk with unnecessary snapshots. Can I delete a snapshot simply by deleting the snapshot file on disk or is it necessary (desirable?) to use a menu item to do so?

[ngeezer]

Solved the first problem. Ran windows 8.1 for some old s/w and noticed that the icon bar was present. In trying to determine the difference in the 8.1 and 10 windows, I finally determined that the icon bar is only visible when running in "full screen" or "seamless" mode. I like "scaled" mode". Switched to seamless mode for windows 10 and the icon bar was back. But then now that I have gotten accustomed to the was things were, I don't mind not having the icon bar.

[mpack]

Please ask one question per topic.