Mediawiki 1.37 - VisualEditor - "Error contacting the Parsoid/RESTBase server: (curl error: 28) Timeout was reached" (sometimes not always) - rest

Question

Please help, I am stuck. :)
I've searched related threads which could not help me.
My version of Mediawiki is 1.37.2
While editing a page with VisualEditor, I sometimes get the following error (Sometimes it works, sometimes I get the error ; it can work 10 times in a row and then don't work):
"Error contacting the Parsoid/RESTBase server: (curl error: 28) Timeout was reached"
The error seems to occur whatever the page size. It happens on any page.
Note: I do not have this error on another test server with the same configuation.
In the log file I get :
[http] HTTP start: GET https://example.com/wiki/rest.php/example.com/v3/page/html/Language%2FMultiple-languages/129917?redirect=false&stash=true
[http] Error fetching URL "https://example.com/wiki/rest.php/example.com/v3/page/html/Language%2FMultiple-languages/129917?redirect=false&stash=true":
(curl error: 28) Timeout was reached
I also sometimes get a timeout error when using this url directely in a browser:
https://example.com/wiki/api.php?action=visualeditor&paction=parse&page=Language/Multiple-languages
I never get an error if I do (using SSH):
curl https://example.com/wiki/rest.php/example.com/v3/page/html/Language%2FMultiple-languages/129917?redirect=false&stash=true
or
curl https://example.com/wiki/api.php?action=visualeditor&paction=parse&page=Language/Multiple-languages
My config in LocalSettings.php
wfLoadExtension( 'VisualEditor' );
$wgDefaultUserOptions['visualeditor-enable'] = 1;
$wgDefaultUserOptions['visualeditor-editor'] = "visualeditor";
$wgGroupPermissions['*']['read'] = true;
$wgGroupPermissions['*']['edit'] = true;
$wgGroupPermissions['*']['writeapi'] = true;

Answer 1

Add to hosts file: 127.0.0.1 example.com