wrote...
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Looking at the script below, when cell A1 is merged with another cell, the
script doesn't work.

Helps if you mention how it doesn't work.

How do i make it work, (irregardless wether its merge or not)

What are you trying to do? Merged cells interact oddly with event
handlers. If you make an entry into a merged cell, the Target range
passed to the event handler is the single top-left cell of the merged
range. However, if you CLEAR a merged cell, the Target range passed to
the event handler is the entire merged range. PITA.