[plt-scheme] MrEd: disabling panel breaks strings

When I disable a panel, the text strings contained in the panel are
truncated, although the panel itself is not resized. Moreover, the strings
are not cleanly truncated at a character boundary, but seem to be partially
overwritten with background pixels. Is this a known problem? Is there a
workaround available? Thanks in advance.

Regards

Michael Burschik