Problem with inserting some characters in MySQL

I’m trying to insert text into the database with some specific characters, like: ← → ∞ ×.
The entry in the database appears, but all these characters are replaced by question marks.
The database itself is in utf-general-ci, the scripts are also in utf-8.
If I try to add an entry with these characters via phpMyAdminI get a warning:

Warning: #1366 Incorrect string value: ‘xE2x86x90xE2x86x92’ for column ‘content’ at row 1

How do I insert these symbols?

Answer 1, authority 100%

Use MySQL encoding – utf8mb4. Characters will be stored as 4 bytes.
utf8_general_cistores characters as 3 bytes and an error occurs when you insert a 4 bytes character.

The correct setting is

Answer 2

Maybe this will help you:

Answer 3

This seems to be a phpMyAdmin issue. Or used to exist see