When using the

{html} macro, switching between rich text and wiki markup editing causes "return true;" to be added to the beginning of "onmouseover" events, effectively stopping any function calls from getting submitted.

Steps to reproduce:
Add the following in wiki text:{html}

<a href="" onmouseover="helloworld();return true;">test</a>

{html}

Change editor to rich text, change back to wiki text, and the page now says:{html}

<a href="" onmouseover="return true;helloworld();return true;">test</a>

{html}

This is primarily a problem when editing pages because I like to keep my default editor as rich text and only change to wiki markup when necessary. But this requires me to remember to change my default editor before editing a page with {html}

and onmouseover or I risk all onmouseover events (at least all <a href> mouseover events) simply returning "true" rather than the actual function they should be calling.