webtextedit clientsideevent javascript - can't eval

webtextedit clientsideevent govern javascript matter mousemove event.
i successfully change impression another vigilant form webtextedit clientside mousemove event:

document.getelementbyid("object2").style.backgroundcolor = '#f0f5f7';

but i wish change impression webtextedit control:

document.getelementbyid("webtextedit1").style.backgroundcolor = '#f0f5f7'; 

then zero happens.

when i govern book same webtextedit clientside another vigilant webtextedit:

object2.style.border='1px plain #ffe6a0'; 

then works. nonetheless i wish change webtextedit clientside style:

webtextedit1.style.border='1px plain #ffe6a0';

then i error:

can't eval webtextedit1.style.border='1px plain #ffe6a0';