Hi, Since Pharo 2.0 on Linux (20599) i have strange behavior when i'm trying to debug a method step by step. Step to reproduce : 1. Create a new Package 'TEST' 2. Create a new subclass 'Test' 3. Create a method 'Validation' Validation |col| col := OrderedCollection new. col add: '1'. col add: '2'. col add: '3'. 4. Add a breakpoint on this method. 5. Open a workspace 6. Write on it : Test new validation. 7. Alt-d to do it A debugger window appear. I choose 'debug' and then choose my method. I can see my code in the window. Normally when you click on 'Over' you can go step by step through your instructions. In 1.4 next instruction was highlighted, but not in 2.0 and 3.0. So you can't see what is done. This feature in 1.4 save me a lot of time fighting bugs and learn smalltalk. Is this a bug ? someone has already seen that ? Regards, Xavier.