Archived topic
WP 4.9 upgrade "Argument #_ is not an array in .../widgets.php on line_" error
12 replies · Started by Ria on November 17, 2017
After upgrading to WP 4.9 I'm now getting an error when navigating to the Appearance/Widgets area within the Dashboard. This is a fresh install on a local development site with the latest GP 1.4 and GP 1.5.3 premium plugin. GP Premium is the ONLY plugin activated.
Here is a screenshot: 
Might be worth reporting here: https://wordpress.org/support/topic/widgets-doesnt-work-with-wp-4-9/
The more people report it, the more likely WP will take notice.
Hey Tom,
I'll certainly do that. But just for the record, I've tested this with other themes, including the default Twenty Seventeen theme, and everything works fine. It's only with my GP setups that I'm experiencing this issue.
The poster in that topic is getting identical errors (even down to the lines in the code). I suppose they could be using GP, but it's not likely.
When you switch to Twenty Seventeen, do any of the widget areas have widgets in them?
When I switch to other themes, including Twenty Seventeen, all is well and the widgets are all there, with no errors.
And when you activate GeneratePress, are there any widgets active in the widget areas?
Yes.
Hmm, I wonder if something was corrupted in your update. Can you try removing all of the widgets, then reloading the page?
Hi Tom,
I rolled back to WP 4.83 and then manually updated to WP 4.9 with from the download from wordpress.org. I had the same issues. I rolled back to WP 4.83 again and did the automatic update from within Dashboard, and same issues.
I removed all widgets from all widget areas and I'm still having the same issues. Here is a screen shot:
Definitely looks like a WP 4.9 bug that they thought they fixed a couple months back during testing: https://core.trac.wordpress.org/ticket/39693#comment:63
The reason it's theme specific for you is the problem function is theme specific - it attempts to retrieve widgets specific to the current theme and place them in the correct areas. From what I can see, it should only happen on theme change, so I'm not sure why it's persisting for you.
Keep an eye on that topic I mentioned - I'll also try to get some core developers eyes on it.
Ok will do. Thanks, Tom.
Ah, someone already reported. Looks like it's already patched and will ship in WP 4.9.1: https://core.trac.wordpress.org/ticket/42603
Oh! That's good news! Thanks! I'll be looking forward to 4.9.1
