Hi Lamday,
I installed the old versions (5.0, 4.9, 4.8) but the problem is not resolved. On another platform, I changed the communication protocol from https to http to line 17 in the jetpack.php file and seems to work all over again.
This may be the problem (maybe an incompatibility with WordPress version 4.8) or is it just a case?
Hosting the two platforms is the same.
original:
/*defined( ‘JETPACK__API_BASE’ ) or define( ‘JETPACK__API_BASE’, ‘https://jetpack.wordpress.com/jetpack.’ );*/
edited:
/*defined( ‘JETPACK__API_BASE’ ) or define( ‘JETPACK__API_BASE’, ‘https://jetpack.wordpress.com/jetpack.’ );*/
Thank you