Quanta using 90%+ CPU

Hello!

I did not use Quanta for a while but recently, i.e. I think with the update to 
3.5.7, I get it using 90%+ CPU for an increasing amount of time. The longer I 
edit files, the longer the "pauses" become.

They happen after adding text to a file, no matter whether it is a CSS or PHP 
file. I disabled the highlighting which did not help. I use a 1.4GHz CPU with 
1.5 GB of RAM, so editing files with ~1000 lines of PHP code should not be an 
issue.

I have no clue what else I could disable to work around that bug or what is 
causing it. It also happens when I close or open a file. After 15 minutes I 
cannot work with Quanta anymore since every pause lasts up to 15-20 seconds. 
After restarting Quanta editing the same files works perfectly, until the 
pauses start to kick in again.

Anyone else experiencing this?

Sven