Even the 6.1 version causes serious problems. After upgrading WordPress to the latest version and the Custom Contact Forms to 6.1, I received a message that asks if I just upgraded and that I should use the upgrade button to upgrade my database for compatibility reasons. I pressed the button, it ran for a while, and below is what I get, I tried it on several different sites I run, and this is a common occurrence. Downloading the older version of the plugin and restoring a backup brought all my forms back, but there must be a better way forward to support your users, we can’t all go recreating every form we’ve ever made.
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