WebShare Api changes file name to random in Andoroid

Question

When I try official WebShare Api level 2 file sharing demos on my Android mobile instead of original file name as attached file in Gmail I have random file name: share7267109384739205738.jpg. There are 19 random numbers after "share"and they changes every time I repeat the process. First I think I did wrong my code (in my project) but on Google and WPT sites with official examples occured the same.

Obviosly it´s a bug because I repeated the error on various andoroid mobiles (version 11 etc.)

Please if any of you has android mobile try these links, they are all official, and tell me if it is true.

On Apple mobiles there is NO problem, the attached file name is correct (in my code too), only android.

Here are links to check it

1.WPT official site example

2. Chromestatus.com example

3. GitHub example

I am confused because I saw this bug on all android mobiles I tried ( 6 different phones, Samsung, Xiaomi etc.) which makes this API useless for billions of users and still nobody neither reacted nor solved it.

Thanks in advance