Gmail has limits to the length of filter queries that seems to be tied to mail's 'search' feature. If the filter 'To' category has a list of addresses separated by an OR operator, Gmail will give the message
The specified search is too long. Please specify shorter advanced search criteria.
The filter does not apply although Gmail does not notify the user and can save the filter. It will not work as a filter and the only way to identify the issue is when searching the filter selection criteria, where at that point you get the error message. If I were to modify an XML file to create Gmail filters, will the limitation on search length still apply?