How to troubleshoot missing srcset and sizes

Hi. If you’re seeing that script line, then the plugin has loaded on your site. There are two things that you should notice once the plugin has been enabled:

1) When you create a new post and add an image to that post, the image should include two new attributes, a srcset attribute and a sizes attribute. This will not be the case with posts you created before activating the plugin.

2) Any featured images you have on your blog homepage (or other places in your site) should also include those attributes.

If either of these aren’t working, then something (either another plugin or your theme) is conflicting with the plugin. If you’ve turned off other plugins and cleared your cache, then I would suspect something with the theme.

We don’t currently have a troubleshooting guide, but that’s a great idea. The plugin development happens over at https://github.com/ResponsiveImagesCG/wp-tevko-responsive-images/ and we’d be happy to get contributions.

Okay it doesn’t seem to markup images as expected, even for new images and new posts. So, let me as some more questions:

(1) Looking at the code — I’m unfamiliar with both PHP and WordPress’s architecture — it looks like the attributes get added only when the image gets added in the editor window. Is that a correct reading? If a post comes through xml rpc complete with <img> tags, is the plugin still supposed to update it?
(2) I’m using Markdown. Do you know if anyone has successfully used this plugin in a blog where all the posts are (and remain) markdown?

Thanks!

Hello again. So, if I understand the question properly, you’re using markdown for the images in your posts, like so:

![Alt text](/path/to/img.jpg)

If that’s the case, then, no, this plugin isn’t going to work for you out of the box at the moment because we are currently not filtering post content in order to add the extra markup.

If you’re using Markdown for the content of your posts but are inserting the images using the ‘Add Media’ modal, then you should be seeing the proper markup. Additionally, you should be seeing srcset and sizes attributes on any instance of a featured image or post thumbnail on the front end. If this isn’t the case then there may be something else going on.

Getting closer!

I created a new post in the editor and added an image via ‘Add Media’. This worked — I see sizes and srcset.

In my normal workflow, I don’t use the MD syntax for images as you reference above (![]()), I stick in <img> tags, usually with some styling. Should those get rewritten?

In addition, do you expect <img> tags coming in through xmlrpc (I write using MarsEdit and never use the web editor) to get rewritten. I also use the markup-to-featured-image plugin rather than setting a featured image in the editor.

Thanks,

Hey TC – sorry for the delay. At this point, the only times content images get rewritten is when they’re added to posts via the media panel, so any markup that you’re adding manually won’t be changed. We’ve decided that for the time being, we didn’t want to risk rewriting people’s content in case someone was intentionally trying to control their own markup formatting.

Hope that makes sense.