Conflict

Attention

[[BaseUserMapping_666][]] is editing TWiki.TinyTextareaPlugin.

has been editing the topic for 1 hour and the lease is still active for another edit.

It is probably OK to go ahead and edit - unless you intend to change data in a form attached to the topic. If actually does save the topic while you are editing, your changes will be merged, and nothing will be lost. Form data cannot easily be merged though, so in this case you are recommended to check with first.