Hangs while doing Search/Replace

I am trying to do a search and replace on the results of a query with 7000 rows. It does a few hundred replaces and then hangs. I am using the latest HeidiSQL. 10.1.0.5464 I have to close the program to recover.

My replace is looking for " NSW" (which is at the end of a field) and replace it with nothing. ie stripping the NSW off the end of each field.

I have repeated the hanging at least four times.