When adding a feed from Google Alerts, the subscribed URL is corrupted, giving an empty feed and a 404 when following the link. On editing the feed, the feed URL is correct but the Site URL has dropped the last part of the URL. So correct URL is something like https://www.google.com/alerts/feeds/01234567890123456789/9876543210987654321 but the resulting Site URL is https://www.google.com/alerts/feeds/01234567890123456789/
Checking on myfeedsucks there’s no issue.
Workaround: Either enter the URL as https://www.google.com/alerts/feeds/01234567890123456789/9876543210987654321/ (note the addition of a trailing slash) or correct the Site URL (with or without slash).
Centos 7.6, PHP 7.1.4, PostgreSQL 9.2.24, tt-rss 782eda4