Simple Debug Info Panel shows a little box on your site with helpful debugging info for developers: post/page ID, which template is being used, etc.
Simple Debug Info Panel for WordPress will enable you to instantly see some “under-the-hood” debugging info for your site. With one click (or none at all), you can see which template is being used, what the post/page ID is, the current screen/viewport size, any categories a post is assigned to, and some more.
Every item’s visibility can be turned on or off, so you have complete control over what will be shown in the infobox.
Within the WordPress structure, only POSTS and PAGES have IDs (including Custom Post Types). Archive pages simply don’t. Any page that lists more than one post/page (or excerpts of those) is considered an archive page. Examples are date archives, author archives, category archives, tag archives, search results, etc.
It’s possible that the dimensions shown in the info box are larger than the actual width/height of the page. However, keep in mind that the dimensions displayed are INCLUDING the scrollbar(s). So, if the page has a scrollbar on the right, and the contents are 700 pixels wide, the infobox will say it’s 716 or so.
Why? Because media queries also take the scrollbar into consideration when calculating width. If there’s a media query breakpoint set at (say) 700 pixels, this point will be met when the contents of the body are actually around 684 pixels, because the screen itself is 684 plus 16 for the scrollbar = 700. Since the scrollbar-included dimensions of the page are important when it comes to responsive design, the dimensions in the infobox also include the scrollbar — very relevant to any media queries.
No, not in the current version. I’ll check if that can be done easily in a future version.
The plugin’s own page can be found here. If that still doesn’t help you solve your issue, please do NOT file a bug through the form on my website, but instead go to the plugin’s WordPress.org support forum.
It’s very possible, or even likely, that something’s not right; I can only do so much testing and it’s impossible to test the plugin with every single theme out there, so there’s a good chance that it will have some issues with themes that I haven’t tested. Please report any bugs on the plugin’s WordPress.org support forum.