x and y words exposed

i've been defining variables x y z in my startup file for a while now, but recent versions of gforth report a redefinition warning for x and y.  ("recent" is from late 2018, perhaps october.)  the conflicting definition for x is reported to be:
    current/unix/jni-helper.fs:80:1
line 81 conflicts with y.

i'm surprised at such short names being globally exposed, especially from something which seems quite optional; the comment at top of file reads, "show/hide keyboard using jni tools".  should i care about this?  is the only problem the untidy warning on startup, or could it hinder my use of jni features?  if i ever get that far. :)