ebook-viewer has lost its borders and much of its functionality

I use calibre on current arch linux. Recently I noticed that ebook-viewer has changed its appearance and lost much of its functionality. It has lost its border with all the menu buttons, leaving only the text window, and while it responds to PgUp and PgDown and arrow keys, it no longer responds to Ctrl-Q to quit. The only way I have found to close it out is as follows
It does not respond to pkill pgrep or an unforced kill command.
Bearing in mind the calibre site's admonition not to trust one's distro's calibre package, I uninstalled arch's version of calibre, and reinstalled it directly from calibre's download site only to find it exactly the same as the arch version.

I really don't mind this stripped down version, it still works fine for reading ebooks, but does anyone know a convenient method of closing it out, or should I just write me a bash function to automate the above commands?