Win10/Office 365 Personal

Graph--Chart Tools/Format/Select textbox, click within the graph, open the text box, type 1 character, click outside the graph to close editing and Excel crashes.

When Excel restarts, the 'saved' pre-crash sheet does not (repairs) show the last action (text box).

I tried booting the machine but the problem persists.

Suggestion?

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Tried again this a.m.--only difference was clicking outside the text box yet within the graph to close the box instead of clicking outside the graph--no crash. I doubt this was the cause of the above problem but I'll take the result.

Mark