Something about how I installed squirrelmail on my kubuntu 16.04 server is not right. After I log into squirrelmail, the webmail.php creates a display with two empty frames. If I browse to right_main.php (or left_main.php) those pages display correctly and the plugin scripts, such as /plugins/fetch_mail/fetch.php also work correctly. Unfortunately, sendmail, i.e. the compose.php script, also does not work. I'm stumped after spending many hours trying to fix this. Tried installing roundcube as a workaround, but it doesn't work right either. Any assistance is greatly appreciated
Is the page that contains the iframe loaded trough SSL and squirrelmail not? Then you have to run squirrelmail under ssl as well, or your browser will not show the iframe content.
