To reproduce it
1. Open Dev Tools > Groovy > Groovy Console
2. Open Apps > Pages
3. Press 0
4. You should be back to Groovy console now, so press 0 again
Notice that this is not always reproducible as the previous fix relied on skipping shortcuts when the DOM element containing the Groovy console has the focus which sometimes is the case, sometimes not, although we tried to force focus onto console in different ways (see related issues comments and commits) none of which proved completely reliable so far.