WordPress hangs when updating a post

Site url?

https://www.openorchestra.org.uk/

Front end looks fine as far as I can tell.

I can’t see anything suspiciously hack-like in the page source – which would have been my initial concern, so it’s down to going through the usual troubleshooting steps:

– deactivating all plugins to see if this resolves the problem. If this works, re-activate the plugins one by one until you find the problematic plugin(s).

– switching to the default theme to rule out any theme-specific problems.

– resetting the plugins folder by FTP or phpMyAdmin. Sometimes, an apparently inactive plugin can still cause problems.

– re-uploading the wp-admin and wp-includes folders from a fresh download of WordPress.

– increasing the memory available to PHP.
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