Bug overview
When submitting a forum post with a blank title, the wrong error is returned.

What part(s) of the site page(s) are affected?
Forum/new

What is the expected behavior?
"Title is missing" error returned.

What actual behavior is given instead?
"Cannot post the same thread twice in a row" (paraphrased) is returned, and it displays the last forum post made by you.

Time of incident (if applicable).
Time of posting.

Can you reproduce the bug every time?
No, I can't seem to reproduce it anymore.

What steps did you take to replicate this bug?
1. Create new topic
2. Leave title blank, add a body, and click Save
3. Error occurs

When it happened to me, my last post was in forum #206862. I then attempted to create a new topic in category #11. When the title was left blank, it gave me the error and displayed my post in forum #206862.

Errors or other messages returned (if any).
"Cannot post the same thread twice in a row" (paraphrased)

strange...but confirmed as i tested it just now to see what would happen (curiosity...).

and can replicate the effect by going back to the "new topic" page and repeating the actions described here.

I was able to replicate this error 2 days ago when making my API question thread, but didn't think too much of it.