Mailster v1.7.7 fixes a few issues.

Most notably, it fixes a bug that was displayed as "1366 Incorrect string value".
This came down to the combination of email content (containing emojis and/or special text characters) with a MySQL database with an inadequate collation setting (or at least for the Mailster tables).
That means a database that is not set up in a way that it can store "new characters" like Emojis. Mailster v1.7.7 automatically fixes/adjusts the database tables to whatever the Joomla content title is configured to use for the collation. This usually means that emojis etc. are then supported and the error is gone.

Improvements

• Update Html2Text library
• Changing install script to use utf8mb4 instead of utf8 for the default character set

Fixes

• Fix for better SMTP debugging
• Fix issue when no iconv functionality is available for charset conversion
• Fix issue to automatically use the core's DB field collation (of content.title) for Mailster's content fields.
  This should prevent the MySQL error "1366 Incorrect string value" when emojis and other utf8mb4 characters are used and the database collation is/was still utf8.
• Do not show unmoderated view in frontend (chronological email view)
• Remove irrelevant code