I've had several incidents where I've marked two lines with
ma
mb
and then tried to move them with
'a,'bm.
and it's inserted a few lines of NUL characters.  If I "u"ndo it, then perform
the same action again, it works fine.  It started with i386-1.0a I believe.
Anyone else experience this?

There is always a similar (same?) number of NULs (maybe 256? just a guess) and
they are always NUL.  I never checked the width of the lines, or the exact
count of the NUL chars.  Of course, it could be just about any pointer-related
problem as well :)
Note that the "moved" text is completely replaced by the NULs, not simply
appended-to.
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