[Plugin: About Me widget] No TinyMCE; "WordPress Failure Notice"

Two problems I’m having:
1) TinyMCE editor is not working (that is, there’s just a plain ‘ole text box showing up in the widget settings, no TinyMCE editor anywhere in sight).
2) When I click the Save button, the entire screen refreshes with a “WordPress Failure Notice,” asking “Are you sure you want to do this? Please try again.” None of the content entered gets saved.

https://www.ads-software.com/extend/plugins/about-me-widget/