There is a problem with wpForo (not sure if this is due to the updated version or older).
When wpForo is activated, i can't edit using Appearance / Editor. When saving, it looks stuck and after 2 minutes i get:
Unable to communicate back with site to check for fatal errors, so the PHP change was reverted. You will need to upload your PHP file change by some other means, such as by using SFTP.
(a lot of people has that with several plugins, so i found wpForo by disabling/enabling my plugins)
I don't see any information related to editing files in the post you've mentioned:
This issue maybe related to "loopback". We'll continue to check it.
The first thing to do is contact your hosting company and ask the hosting support team to check the following points :
- Make sure your server is running a recent version of PHP and the cURL library.
- Try to increase your Server Memory Limits settings.
- The cURL error can be a dns related issue. Your hosting company might need to switch dns configuration to OpenDNS : https://www.howtogeek.com/164981/how-to-switch-to-opendns-or-google-dns-to-speed-up-web-browsing/
- Ask your host if there is some limitation with wp-cron, or if loopback is disabled.
- Ask your host if there a firewall or security modules (e.g. mod_security ) that could block the outgoing cURL requests.
@robert i will not do the above. Nothing wrong with all that. I even disabled mod_security just in case. No luck.
The problem occurs only when wpForo is activated. I could say that it is a conflict between plugins, BUT the problem also happens in my empty-no-plugins WP test site.
The only thing i will (try to) do is ask my hosting company to check if they see any more details for the original error at the top, since my debug.log is empty.
It seems that this is all over the Internet for several WP Plugins. Most of them had this issue:
In most cases, the issue lies with an open “session_start()” function being called unconditionally, meaning that the plugin or theme is trying to initiate PHP Sessions everywhere on the site, instead of strictly where it is needed. WordPress does not use PHP Sessions, and as such sessions should not be initiated on the editor pages.