WhatsApp also scans pdf files you send to a contact. Easy to confirm as well: get some random pdf with chinese filename and chinese content. Send it to a contact. Watch the delay in send/receive. Now do the same for any random pdf that's all English. Watch the regular send/receive time occur.
The only conclusion: it takes a little time for a file that's flagged - based on its language - to pass the scanners?
The only conclusion: it takes a little time for a file that's flagged - based on its language - to pass the scanners?