I think the JavaScript event, if you were to do things things that way, is onMouseOver.

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I've given up with my rich text box search btw. I don't seem to be able to find one which is quite right... Oh well, have fixed a couple of problems and got threads attempting to detect abc so posting something like this:

X:1
T:Paddy O'Rafferty
C:Trad.
M:6/8
K:D
dff cee | def gfe | dff cee | dfe dBA |
dff cee | def gfe |faf gfe |1 dfe dBA:|2 dfe dcB |]
~A3 B3 | gfe fdB | AFA B2c | dfe dcB |
~A3 ~B3 | efe efg |faf gfe |1 dfe dcB:|2 dfe dBA |]
fAA eAA | def gfe | fAA eAA | dfe dBA |
fAA eAA | def gfe |faf gfe | dfe dBA:|

can (browser, edit control, etc. permitting...) produce this which is a bit better...