for some triggers, pressing "toggle input method" link results in this link being removed, but advanced editor controls still to not appear. example trigger expression :

{Host:vfs.file.exists[/tmp/file1].last(0)}

=

{Host:vfs.file.exists[/tmp/file2].last(0)}

that's probably because trigger editor does not consider that a valid expression, but it should not just disappear like that