The member has turned on private topic notifications and the notification itself (saved in actual content - a private topic) contains a mention. I'm not sure the precise scenario, but essentially it is an infinite loop.
Composr parses all its Comcode for something posted, keeps separate note of mentions found, and says to send out mention notifications for everything picked up. However if a member had the mention notification go to a private topic, that would post and Composr would again send out mention notifications for everything already noted - restarting the same send loop of just one member mention notification but in a deeper level of code recursion. That happened until the maximum recursion depth limit in PHP was hit.
The member has turned on private topic notifications and the notification itself (saved in actual content - a private topic) contains a mention. I'm not sure the precise scenario, but essentially it is an infinite loop.
Working on a fix...
Specifically, the bug...
Composr parses all its Comcode for something posted, keeps separate note of mentions found, and says to send out mention notifications for everything picked up. However if a member had the mention notification go to a private topic, that would post and Composr would again send out mention notifications for everything already noted - restarting the same send loop of just one member mention notification but in a deeper level of code recursion. That happened until the maximum recursion depth limit in PHP was hit.