Dto2ExtJS generates js classes with dto2extjs comment and timestamp as first line of a file. It's not very convenient for VCS systems because each developers would have files with came classes but different timestamp in comments. That will cause conflicts during merge.
https://github.com/Farata/ClearJS/blob/master/cdb.dto2extjs.plugin/xslt/js-ext-js-class-generated.xslt#L27