Comment 5 for bug 157866

This bug was fixed some day ago. Thanks for your testing. To cleanup
the tag array I register for ItemDelete events with the tree widget
that does the cleanup automatically, like:

    # This automatically cleans up the tag array.
    $T notify bind UsersTreeTag <ItemDelete> {
 foreach item %i {
     ::GroupChat::TreeUnsetTags %T $item
    bindtags $T [concat UsersTreeTag [bindtags $T]]


proc ::GroupChat::TreeUnsetTags {T item} {
    variable tag2item

    set tag [$T item element cget $item cTag eText -text]
    unset -nocomplain tag2item($T,$tag)

The docs:
If any items are going to be deleted, then an <ItemDelete> event event
is generated just before the items are deleted.

 So I think it should be OK.