I've done some searching, nothing similar coming up so I thought I'd ask in the slim hope that someone has either already seen this behaviour, or recognises the symptom, goes to check after reading this and discovers that they too have this glitch!
We are finding that occasionally, intermittently, placeholders in a random page will be discovered to have spawned a twin. The content classes on which the page is based continue to show just the single placeholder.
This has affected a variety of pages in a variety of projects on both our development and live servers. There doesn't seem to be any consistency to the issue: sometimes just one placeholder is duplicated, sometimes more. On one occasion every single content and structural element of a single page had duplicated itself.
We're struggling to make sense of it: all we know is that as if by magic a page will suddenly drop its content because the duplicate placeholder takes over as the "real" one and is empty. This afternoon was the ultimate kicker as the duplication affected the start page containing all the global reference elements for the project - bam, the whole project useless in a single click.
Naturally we're in conversation with OT Support (hello Lee, Adam) but without a firm method of replicating the issue, we're not able to give them much to work with. I thought I'd widen the range of our pleas for help. We cannot realistically progress with Phase II of our institution-wide migration with an intermittent bug like this hiding in the shadows waiting to pop out and steal a customers' content.
Our team has already fielded several complaints about this issue, and up until now we've muddled through by copying the content from the superceded "original" placeholder to its evil twin, but that's not a long-term solution.
Thanks in advance for any insight.