Gem files locked for updating.

I sometimes find bugs in the gems used in Rails projects.  I like to be able to edit the files directly to see if it fixes things.  When I upgraded to RM 5.4 from 4.0.1, I can no longer edit some gem files.

I can search and find the files but when I open them there is a little lock icon(see attached), and I can't edit them.  This is not the case in RM 4.  Also, I changed the permissions on the file to 777, so that doesn't seem to be the issue.

Is there a setting or something to allow editing of "non-project" files.

Thanks in advance,

Derek