[RCU] Logins fail after 1.3.0 upgrade; work on 1.2.5

I have Roundcube checked out from git. When I from upgrade from 1.2.5 to 1.3.0 (git checkout 1.3.0), logins fail with the "Invalid request! No data was saved." error. Reverting to 1.2.5 (git checkout 1.2.5) allows logins to occur successfully.

I tried the following, with no effect:

• Running bin/install-jsdeps.sh, bin/installto.sh, bin/indexcontacts.sh and

bin/cleandb.sh

• Enabling both $config['force_https'] and $config['use_https']
• Enabling only $config['force_https']
• Truncating the session and cache_* tables

Logs: nothing is added to logs/imap when these failures occur; logs/sql shows an INSERT to the session table

config:

• Ubuntu 16.04.2
• dovecot 2.2.22
• apache 2.4.18
• postfix 3.1.0

$config['default_port'] = 993; $config['default_host'] = 'ssl://myhostname.com';

Paul