UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.45 Safari/537.36

Steps to reproduce the problem:
1. Configure font size setting in options to "12".
2. Invoke Secure Shell window and Connect to a remote machine.

What is the expected behavior?
Font size stays at selected value of 12.

What went wrong?
Font switches itself back to 14 after "Loading NaCl plugin... done." step while connecting.

Something also gets corrupted in the display such that the console still seems to think it has more rows/cols than it actually does; for example, tmux's footer line wraps around past the end of the righthand side of the terminal and overwrites part of the lefthand side of the same footer line, like
  s.mtv.corp." 12:08 08-Oct-18                                                                        "dbarnett-w
instead of
  [ssh] 0:bash- 1:bash*                                                                    "dbarnett-ws.mtv.corp." 12:08 08-Oct-18

If I manually decrease the font size back, then everything goes back to working as intended for that connection session.

WebStore page: https://chrome.google.com/webstore/detail/secure-shell-app/pnhechapfaindjhompbnflcldabbghjo

Did this work before? N/A 

Chrome version: 70.0.3538.45  Channel: beta
OS Version: Debian Testing
Flash Version: 

I found a few potentially related bugs reported like #802087, but not quite the same cause/effects. This is not using web fonts or overriding any other settings besides font-size AFAIK.