Yes, this is fixed in P7��https://pharo.fogbugz.com/f/cases/20212#BugEvent.193460solution is to close your image and open again, or go to process browser and kill the new UI loop that started.As a workaround you can do parseExpression:onError: (or whatever the name is)... or I've made a small wrapper which doesn't suffer from thsi��https://github.com/peteruhnak/pharo-changes-builderPeterOn Wed, Oct 17, 2018 at 5:00 PM Dimitris Chloupis <kilon.alios@gmail.com> wrote:If I do something normal in the Playground likeRBParser parseExpression: 'bac' and inspect it , it works fineIf I do something likeRBParser parseExpression: 'bac->'. Then it displays an error and things really get weirdI get redraw problems with Morphic(if I start moving windows around), with windows leaving trailing images behind and Pharo slowing down.Can anyone reproduce my problem ?I can reproduce this behavior in 6.1 32 bit and 64 bit and with other incorrect syntax strings.