Suppress deprecated notices

As mmm stated:

in which file appears the first notice?

Wherever the notice is mentioning the location of this deprecated function (path/to/some/file.php), you would insert the following just below the <?php tag which starts off the file:

error_reporting(0);

I’ve tried the above functions you mentioned and inserted them in my wp-config.php when I experience something similar, but they didn’t work for me. This will turn off warning, deprecated, and everything else except the errors.