I've tried this on Firefox and Chrome and have been able to reproduce it consistently.

Repro Steps:

- Copy an image and paste into web decker. Make a selection using the Lasso tool and hit delete. This should freeze decker to the point where you have to refresh the page.

Console Errors:

Uncaught TypeError: dr.mask is null     bg_end_lasso https://beyondloom.com/decker/tour.html:6510     bg_delete_selection https://beyondloom.com/decker/tour.html:6524     <anonymous> https://beyondloom.com/decker/tour.html:7597 tour.html:6510:123     bg_end_lasso https://beyondloom.com/decker/tour.html:6510     bg_delete_selection https://beyondloom.com/decker/tour.html:6524     <anonymous> https://beyondloom.com/decker/tour.html:7597</anonymous></anonymous>
Uncaught TypeError: dr.mask is null     bg_end_lasso https://beyondloom.com/decker/tour.html:6510     setmode https://beyondloom.com/decker/tour.html:4347     settool https://beyondloom.com/decker/tour.html:4408     toolbars https://beyondloom.com/decker/tour.html:6918     toolbar https://beyondloom.com/decker/tour.html:6866     toolbars https://beyondloom.com/decker/tour.html:6911     tick https://beyondloom.com/decker/tour.html:7478     loop https://beyondloom.com/decker/tour.html:7562

Fixed.

Went ahead and rolled this fix out to the instances of web-decker on beyondloom.