Fix comment creation
@lphs11 you already faced this Issue on your dev branch, if i remember right. Now we have to problem on the master.
Visit https://neu.frag.jetzt/participant/room/4367053/comments and watch the console. The creation modal is also bugged.
main-es2015.0bc1296751b269e7a25c.js:1 ERROR TypeError: Cannot read property 'slice' of undefined
at zn (main-es2015.0bc1296751b269e7a25c.js:1)
at Ba (main-es2015.0bc1296751b269e7a25c.js:1)
at Wa (main-es2015.0bc1296751b269e7a25c.js:1)
at main-es2015.0bc1296751b269e7a25c.js:1
at Wa (main-es2015.0bc1296751b269e7a25c.js:1)
at go (main-es2015.0bc1296751b269e7a25c.js:1)
at main-es2015.0bc1296751b269e7a25c.js:1
at Wa (main-es2015.0bc1296751b269e7a25c.js:1)
at go (main-es2015.0bc1296751b269e7a25c.js:1)
at main-es2015.0bc1296751b269e7a25c.js:1