The image in this screenshot is being displayed at 240x135 by the
.IndexImage img
style, but the file is actually being served at its original size of 16522x6190. This is complete futzing up the scrolling on that thread list page. Images should always be resized on the server side - CSS resizing just tells the browser to cram all those pixels together into the smaller space, causing performance issues like this one, as well as bandwidth issues.
I'm not familiar with Vanilla Forums, but Drupal uses a concept called Image Styles that allows you to specify how images are resized/cropped (and more) to fit the various places in which they are to be displayed. When you hit a page like the thread index, it'll look for the resized copy of the image in question and if it doesn't exist, will create the variant from the original and cache it on the server.
Fixing this will make life easier on users, but it'll also save on hosting bandwidth costs.
Posts
I can put in limits for image upload sizes (and probably should at some point to be honest), but that won't really make a difference with externally hosted images like the one in the example. Server side resizing is not something that's available in Vanilla (at least in the Open Source one), and implementing one is probably not a trivial task. Also, the image in question is hosted elsewhere, so nothing we do server side will do much, but I'll see if there is some validation I can do for thumbnail generation for the index.
For what it's worth, I removed image tags from the post, so it shouldn't mess up the user experience, if you stay out of the thread.
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This doesn't really solve your particular issue, since it was a hotlinked image, but the index should be a lot easier on the bandwidth now, since I think most people use attachments.
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