Private Messages to more than one recipient

I didn't know it was possible to send PM's to more than one recipient at a time until yesterday when a two friends and I had a 3-way conversation!

However, can one of you techies please tell me if this facility is limited to the 20 oldest friends on the list? (By old I don't mean age-wise LOL). I have been experimenting and it seems I can use this facility for the 20 people who have been my friends the longest. It doesn't work for any of the people who became my friends after number 20!

Is this the intention, or have I got some gremlins?

Cheers, Linda.

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