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            <b><a class="bz_bug_link 
          bz_status_NEEDINFO "
   title="NEEDINFO - Calc: Bug with copy+paste for joined cells that also breaks Undo/Redo"
   href="https://bugs.documentfoundation.org/show_bug.cgi?id=118559#c13">Comment # 13</a>
              on <a class="bz_bug_link 
          bz_status_NEEDINFO "
   title="NEEDINFO - Calc: Bug with copy+paste for joined cells that also breaks Undo/Redo"
   href="https://bugs.documentfoundation.org/show_bug.cgi?id=118559">bug 118559</a>
              from <span class="vcard"><a class="email" href="mailto:xv3247@gmail.com" title="Xavier Van Wijmeersch <xv3247@gmail.com>"> <span class="fn">Xavier Van Wijmeersch</span></a>
</span></b>
        <pre>Created <span class=""><a href="http://bugs.documentfoundation.org/attachment.cgi?id=143360" name="attach_143360" title="screenshot">attachment 143360</a> <a href="http://bugs.documentfoundation.org/attachment.cgi?id=143360&action=edit" title="screenshot">[details]</a></span>
screenshot

It seems to me that the borders are not correct set, see screenshot.
but when copy the green cell and then pasting to C22:C33; then it will undo in
the next column, the merged cells.
Pressing ctrl+z will reset to the normal state.

Version: 5.3.7.2
Build ID: 6b8ed514a9f8b44d37a1b96673cbbdd077e24059
CPU Threads: 8; OS Version: Linux 4.14; UI Render: default; VCL: kde4; Layout
Engine: new; 
Locale: nl-BE (en_US.UTF-8); Calc: group

Version: 6.2.0.0.alpha0+
Build ID: df8589bd49d7eb1bb42ae78abcb91d33cf9255ce
CPU threads: 8; OS: Linux 4.14; UI render: default; VCL: kde4; 
Locale: nl-BE (en_US.UTF-8); Calc: group threaded</pre>
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