# Post with embedded latex makes channel unusable

#1

#### Summary

A specific post in a direct chat caused the direct chat channel to be unusable until the post was deleted in the database.

#### Steps to reproduce

Using mattermost 4.7.2.
Post the following to a channel:

this:
latex
\begin{eqnarray*}
\Delta\sigma_{R} = \sigma_T - \sigma_I)
\end{eqnarray*}



#### Expected behavior

Channel does not break

#### Observed behavior

All users in that channel saw a blank screen every time they navigated to the channel (whether using the browser or a desktop client). They had to re-open the client/browser to navigate to another channel.

After deleting this post, normal behaviour returned.

#2

Thanks for reaching out. This is a known issue in version 4.7.2 and we released a fix for it in version 4.8 so if you upgrade that should fix it.

#3

I don’t seem to have permission to view that ticket, but thanks - will test it after next upgrade!