post error from cloudflare

[Larz60+]

The only time I see it is if I attempt to respond to a thread using the following sequence.

1. Forums->Unread Posts
   
2. Click on one of the Unread posts
   
3. Quick Reply
   
4. Reply must have a link to some other forum area like Posts to NOT make at all. I chose this at random, can't say it has any association with the help URL
   
5. Click on Preview Post (always occurs during preview), and only in quick reply.
   
6. entire text in Quick reply is erased.
   

If, instead, I use 'New Reply' button, there is no error even with same exact text as attempted in quick reply.
If it's my network, then this is the only site, and/or forum where it occurs. So, even though it's remotely possible, it's unlikely.