Question Empty message window. But message is there!

I use 1.6.0 stable.

Recently users complained that posting does "not work". No matter what you write the message comes out empty. And is not a case of white letters on white background. No mater how many lines is the message, the output is the same height!

Clicking "edit" the message is visible, so the message is not lost.

On the same topic, I can see normal (visible) and "empty" messages. So is not a topic wide problem.
There are no bbCodes or other codes visible in the message. Just plain text.

Ideas?

This sounds like a Joomla plugin problem. My guess is that you have a content or system plugin installed, that does something to the output. Try to disable any 3rd party plugins you have installed. I am fairly certain it will fix the problem.

Thanks for the reply.

This problem appeared without any change to the site.
Also why it affects only some messages and not others or all?
Furthermore some users have posted the same content 2 - 3 times in a row (using copy-paste) and only the last of their post is visible. (which contains the same stuff as the previous invisible messages)

Odd.

I had a better look in the messages.

It seems that if [ or ] is typed somewhere the message will not show. Deleting these characters cures the problem.

Someone else had this problem too. The bug seems to just take effect if the post contains non latin letters.

Correct. The messages contained Greek letters.

It seems that some specific sequence triggers this behavior.

In my case it was something like [Η Λ

See, it also happens here!
So is not only my problem!

Since only the moderators can read the above message i will state again that post contained a sequence of greek letters.

The sequence in this case is [ΗspaceΛ

If you replace the word -space- above with a space the message disappears.

I have exactly the same problem!
Some messages are completely blank although the messages exist in mysql.
Also in "view source" messages are not there!
It can be easily reproduced...
In my case all the blank messages have an img tag like this: If this is removed everything is OK, the message appears again!

Copying that code doesn't break anything for me. Please check your apache log file (just after displaying white page) to see what's going wrong.

After some hours of troubleshooting, I finally spotted the problem.
the problem is in com_kunena/lib/kunena.parser.php:
So, for a quick fix I just disabled the "Trim URL" config option and everything went back to normal!
The thing is that in this case, it should't go there at all, because URLs inside the img tags should not be shortened...\
Am I right?
I am using php 5.3.8 and K1.6.4