but out of a sudden components of WordPress stopped working after the upgrade …
I'm one of this and recently I've upgraded WordPress to 4.8.2, hopeing that this would make my blog even better with the fresh new wordpress but suddenly my Widgets stopped working, e.g.
Appearance -> Widgets
Show me strange blank page, when I tried to debug that in browser, with browser console in Google Chrome and Firefox ESR / Opera with Inspect elements, I could see some partially generated webpage, so I investigated further to see what in reality is creating my WordPress Widget troubles, I tried adding WordPress Debugging in wp-config.php for those who don't know how to do it to do so, you need to add the following line of code to wp-config.php
# vim /var/www/blog/wp-config.php
define( 'WP_DEBUG', true );
define( 'WP_DEBUG_LOG', true );
If everything is fine with your wordpress installation (e.g. directory / file permissions are reporting the fine), The log file should be situated under
But if you enabled debugging like me and nothing was visible neither in WordPress WP generated page, neither in that log or even worse, the file is not being written, that might be an indicator of either a seriously messed wordpress installation, or bugs occuring due to combination of WordPress release with the PHP installed on the server in my case the WordPress was 4.82 and PHP is standard Debian package PHP 5.6.30
The next place I checked logically is HTTPD (Apache) both access and error logs and there I found the widgets.php once called is returning 500 (Internal Server Errors), so I was forced to do something to make my appearance work again.
I tried my best to make Appearance -> Widgets and Appearance -> Customize WP Dashboard menus to work but without success so I finally got pissed off and decided to downgrade WordPress to the previous version where everything was running fine.
A quick investigation in Google led to find that there is an easy to use WordPress plugin that is capable of upgrading / downgrading wordpress to virtually all official WordPress releases.
Below is shortly what I had to do to Downgrade my WP 4.8.2 to WP 4.7.3
1. Download WP Downgrade Specific Core Version wordpress plugin
The plugin “WP Downgrade” forces the WordPress update routine to perform the installation of a specified WordPress release. The Core Release you specify is then downloaded from wordpress.org and installed as would any regular update. You can permanently stay on a previous version of your choice or update selected.
To download the plugin click here, save it to your computer and then transfer to server or directly use wget or curl commands with the exact plugin location and unzip it standardly
# cd /var/www/blog/wp-content/plugins
# wget https://downloads.wordpress.org/plugin/wp-downgrade.zip
# unzip wp-downgrade.zip
N.B. ! On a shared hosting or CPanel, you might have to upload the plugin with FTP.
2. Enable WP Downgrade Specific Core Version wordpress plugin
Plugins -> WP Downgrade Specific Core Version enable
Below is a quote from the plugin website describing more about WP Downgrade plugin:
"WP Downgrade | Specific Core Version has the potential for becoming one of the best-loved plugins among those, who simply cannot update to the latest WP release.
In the past the latest WP release was the only offering for WP’s Automatic Update routine. This left all those behind, who have to wait with Core updates, until their plugins become compatible with newer WP releases. When this finally happens, more often than not there has already been yet another Core update. In the end a dreaded, cumbersome, time-consuming and error-prone Manual Update used to be the only way to go.
With WP Downgrade | Specific Core Version this is now a thing of the past. Anyone who lags behind the latest WP release is now able to use Automatic Updates even to lower WP versions. What WP Downgrade does simply is to make WP believe that the version you want to update to actually is the latest version. Because of this, there is no difference to updating to the latest version."
3. Configure WP Downgrade Specific Core Version plugin
Settings -> WP-Downgrade
4. Install (Downgrade) WordPress to the previous release
Next you will have to press the re-install button to install the desired WordPress release, if you're unsure which was the exact previous version you used you can check the list of All WordPress official released versions here choose any version that was released few months before the latest that was creating troubles for you and do re-install with it, if you face issues with it, you plenty of other versions that are close to it with which you can try, after all one of them should be working.
Assuming that your directory structure of the current installed WordPress is not having any permission issues, the respective version of wordpress would be downloaded and untarred over the actual latest release you're having, so soon you'll have your WP reverted to the OLD release.
Once downgrading in my case immediately my Appearance -> Widgets started working again. Hooray!
Note: that if you face some permission errors during download or install of the downgradable version of wordpress you will be notified, to fix that just take few minutes with chown command and so something like:
chown -R www-data /var/www/blog/
that should fix permissions for you so then you can happily again, re-run the re-Install button to finalize WP Downgrade.
Now you can enjoy your life as everytihng will be working as expected, no broken more strange plugins behavior (which is another additional effect showing incompitability between WordPress release and a Plugin, no nothing), you can sleep calmly again.