November 5th, 2019 Update – This bug remains unfixed in WPBakery version 6.0.5 released on July 17th 2019.
The WPBakery (aka Visual Composer) changeHandler function uses the “vc.accordion” data attribute without first checking for it’s existence. Any plugin or theme using a jQuery show / hide event trigger will trip this bug, and the post editing page will fail to load properly.
I’ve posted a bug report to the Visual Composer channel on Slack, but the channel does not seem to be read by WPBakery employees, so this bug may continue to go unfixed. If you are a WPBakery customer affected by this issue, you may want to report the bug to WPBakery.
The unminified WPBakery code looks like this – notice that the
data("vc.accordion") attribute is being used here without first checking if the attribute actually exists or not.
If you are concerned about the quality of your NextGEN Gallery v2.x resized images, this should be of particular interest to you.
Some months ago I contacted Photocrati to ask them how, in version 2.x, developers could retrieve the “actual” dimensions of a resized image. In the past, after resizing an image we could use PHP’s getimagesize() function on the resulting file, but in v2.x image resizing is dynamic and those resized images may not be available on disk. I had some concerns between the expected / calculated image dimensions, those returned by NGG v2.x’s methods / functions, and the actual image retrieved by the URL. All 3 dimensions were different! A resized uncropped image which should have been 300x200px, was reported as being 300x199px by the NGG methods / functions, and the image retrieved by URL was 298x199px!
This may not sound like much, but a few pixels here and there can lead to image distortion when rendered by browsers, alignment issues in page layouts, and failures when working with minimum image dimensions (for example, Facebook ignores images smaller than 200x200px).