I've been encountering this issue on the site more and more recently, but it seems like if a browser is kept open for too long some images stop loading on D&D Beyond.

When attempting to connect to one of the images directly I get an error "Your request header section exceeds the maximum allowed size".

The issue appears to be that D&D Beyond is accumulating too many cookies in the browser, and when the browser sends all of these they are resulting in a header size larger than the site allows, causing some requests to be rejected. A quick look at cookies shows me a whole mess of "ddb.toast" cookies for various homebrew pages, along with several dozen tracking related cookies, so it's no wonder the header size is growing too large.

As a part time web developer myself there are two simple solutions to this one that I'm aware of:

• Cut down on the dang cookies! There are definitely too many of them, with overly long names and content, though this may be easier said than done. For starters get rid of the homebrew "toast" cookies; they seem to be related to the annoying "you posted your first magic item" or whatever messages which repeat too much as it is. Please store that data with the account instead and ditch the cookies. Cutting down on the tracking cookies wouldn't hurt either.
• Use a sub-domain for images. This is fairly common practice; you put the main site at www.dndbeyond.com then you serve up all images from static.dndbeyond.com or images.dndbeyond.com or whatever; this way browsers won't send any of the www.dndbeyond.com cookies when requesting the images, which keeps the requests small (and saves bandwidth). How easy this is to do depends on your web hosting software but on nginx for example it's fairly easy to add a sub-domain that's identical to the main one (optionally configure it to ignore requests for anything that isn't an image since that's all you want it for). Then all you need to do is change the URLs for affected images to use this sub-domain instead of www.dndbeyond.com.

The images that are most affected for me at least are custom images I've uploaded for character sheet thumbnails, as well as images for homebrew items (I think this may be the thumbnails again), and also sometimes user thumbnails on the forums. I'm assuming main site images, book content etc. already use CDNs or similar so they aren't affected (as they're using a different domain) as I've not noticed any of them failing to load (could be coincidence though).

I can resolve this issue temporarily for myself by clearing all of the sites cookies, but like I say, the site just has so many of them (and loads of them have either long names, long contents or both), so the issue just comes back again after a few days. Closing and reopening my browser also clears some of the cookies, and may get me below the request header limit, but not always.

I assume I'm a bit more susceptible than most because I have a large number of the homebrew related cookies, but I expect regular users are dangerously close to the limit as well if that's all it takes to tip it over the edge, so it's worth fixing regardless.

Sorry to bump this, but the issue is still happening.

However, I think I've found the cookie that is to blame, it's named "Ratings" and seems to be filling up with the word "undefined" over and over again, here's what it currently looks like for me:

Ratings=15%2C4235920%2C1%2Cundefined%7C15%2C4234178%2C1%2Cundefined%7C15%2C4234072%2C1%2Cundefined%7C15%2C4234346%2C1%2Cundefined%7C15%2C4175478%2C2%2Cundefined%7C15%2C4175685%2C7%2Cundefined%7C15%2C4182580%2C3%2Cundefined%7C15%2C2245555%2C1%2Cundefined%7C15%2C2245699%2C1%2Cundefined%7C15%2C2246360%2C3%2Cundefined%7C15%2C2248300%2C1%2Cundefined%7C15%2C4235266%2C2%2Cundefined%7C15%2C4234395%2C1%2Cundefined%7C15%2C4234765%2C1%2Cundefined%7C15%2C4237001%2C1%2Cundefined%7C15%2C4237016%2C1%2Cundefined%7C15%2C4229702%2C2%2Cundefined%7C15%2C4236211%2C1%2Cundefined%7C15%2C4237892%2C1%2Cundefined%7C15%2C1119027%2C50%2Cundefined%7C15%2C4238835%2C2%2Cundefined%7C15%2C2582999%2C2%2Cundefined%7C15%2C4240201%2C1%2Cundefined%7C15%2C4240075%2C1%2Cundefined%7C15%2C4238871%2C2%2Cundefined%7C15%2C4239926%2C2%2Cundefined%7C15%2C4239932%2C1%2Cundefined%7C15%2C4238386%2C1%2Cundefined%7C15%2C4238375%2C3%2Cundefined%7C15%2C4237568%2C1%2Cundefined%7C15%2C4241324%2C1%2Cundefined%7C15%2C4241412%2C1%2Cundefined%7C15%2C4241445%2C3%2Cundefined%7C15%2C4242213%2C3%2Cundefined%7C15%2C4243572%2C2%2Cundefined%7C15%2C4243079%2C1%2Cundefined%7C15%2C4242630%2C3%2Cundefined%7C15%2C4242246%2C3%2Cundefined%7C15%2C4243738%2C1%2Cundefined%7C15%2C4244384%2C1%2Cundefined%7C15%2C4243334%2C1%2Cundefined%7C15%2C20149%2C19%2Cundefined%7C15%2C4242253%2C1%2Cundefined%7C15%2C4240878%2C1%2Cundefined%7C15%2C4241407%2C1%2Cundefined%7C15%2C4244499%2C1%2Cundefined%7C15%2C4244699%2C1%2Cundefined%7C15%2C4244991%2C1%2Cundefined%7C15%2C4244469%2C2%2Cundefined%7C15%2C4245562%2C1%2Cundefined%7C15%2C4245631%2C3%2Cundefined%7C15%2C4246122%2C4%2Cundefined%7C15%2C4246131%2C4%2Cundefined%7C15%2C4246146%2C3%2Cundefined%7C15%2C4246244%2C2%2Cundefined%7C15%2C4246338%2C2%2Cundefined%7C15%2C4246350%2C2%2Cundefined%7C15%2C4246500%2C2%2Cundefined%7C15%2C4246517%2C2%2Cundefined%7C15%2C4246684%2C1%2Cundefined%7C15%2C4239012%2C2%2Cundefined%7C15%2C4245376%2C2%2Cundefined%7C15%2C4214515%2C2%2Cundefined%7C15%2C4215229%2C1%2Cundefined%7C15%2C4245386%2C4%2Cundefined%7C15%2C4245465%2C4%2Cundefined%7C15%2C4244534%2C3%2Cundefined%7C15%2C4244740%2C3%2Cundefined%7C15%2C4247825%2C1%2Cundefined%7C15%2C4247493%2C1%2Cundefined%7C15%2C4244371%2C2%2Cundefined%7C15%2C4250241%2C1%2Cundefined%7C15%2C4270881%2C2%2Cundefined%7C15%2C4271970%2C2%2Cundefined%7C15%2C4283139%2C2%2Cundefined%7C15%2C4283605%2C1%2Cundefined%7C15%2C1151757%2C1%2Cundefined%7C15%2C1151900%2C5%2Cundefined%7C15%2C4280015%2C1%2Cundefined%7C15%2C4280003%2C2%2Cundefined%7C15%2C4280065%2C1%2Cundefined%7C15%2C4277839%2C2%2Cundefined%7C15%2C4285776%2C1%2Cundefined%7C15%2C4285820%2C1%2Cundefined%7C15%2C4127286%2C4%2Cundefined%7C15%2C4121557%2C2%2Cundefined%7C15%2C4122197%2C1%2Cundefined%7C15%2C4290051%2C1%2Cundefined%7C15%2C4289737%2C1%2Cundefined%7C15%2C2191285%2C3%2Cundefined%7C15%2C2192985%2C2%2Cundefined%7C15%2C2192996%2C1%2Cundefined%7C15%2C4289305%2C2%2Cundefined%7C15%2C4290082%2C2%2Cundefined%7C15%2C3213284%2C3%2Cundefined%7C15%2C4272427%2C4%2Cundefined%7C15%2C4277837%2C3%2Cundefined%7C15%2C4253484%2C1%2Cundefined%7C15%2C4253563%2C2%2Cundefined%7C15%2C3751690%2C2%2Cundefined%7C15%2C2169300%2C3%2Cundefined%7C15%2C2172437%2C5%2Cundefined%7C15%2C4281823%2C1%2Cundefined%7C15%2C4281827%2C2%2Cundefined%7C15%2C4247533%2C1%2Cundefined%7C15%2C4247541%2C1%2Cundefined%7C15%2C4290816%2C1%2Cundefined%7C15%2C2559861%2C3%2Cundefined%7C15%2C2561860%2C2%2Cundefined%7C15%2C4292507%2C2%2Cundefined%7C15%2C4294198%2C1%2Cundefined%7C15%2C4293887%2C1%2Cundefined%7C15%2C4297489%2C1%2Cundefined%7C15%2C4297340%2C2%2Cundefined%7C15%2C4297039%2C2%2Cundefined%7C15%2C8697%2C1%2Cundefined%7C15%2C4297370%2C1%2Cundefined%7C15%2C4298269%2C1%2Cundefined%7C15%2C4299872%2C1%2Cundefined%7C15%2C4299377%2C3%2Cundefined%7C15%2C4300727%2C1%2Cundefined%7C15%2C4301195%2C2%2Cundefined%7C15%2C490863%2C3%2Cundefined%7C15%2C4296842%2C2%2Cundefined%7C15%2C4296962%2C3%2Cundefined%7C15%2C4296920%2C3%2Cundefined%7C15%2C4302235%2C2%2Cundefined%7C15%2C4303391%2C2%2Cundefined%7C15%2C4303149%2C1%2Cundefined%7C15%2C3847482%2C2%2Cundefined%7C15%2C3848759%2C3%2Cundefined%7C15%2C4302867%2C2%2Cundefined%7C;

I believe the cookie is related to upvoting on forum posts which means only users who upvote a lot will be affected. I also think it's related to another bug I've noticed, which is that sometimes the forums don't show when I've already upvoted a post (allowing me to "upvote" again but actually I'm removing and adding my vote repeatedly).

If you could pass this info on then hopefully it can be fixed easily, or at least the cookie's expiration time can be reduced or something as a quick fix. Fortunately deleting just this cookie seems to fix both issues (images not loading and forum upvotes going weird) without logging me out, so I can just do that in the meantime.

I hope they are able to switch to using a subdomain to serve up images, I think that would make a big difference.

The cookies would likely still interfere with character sheet PDFs though.

I know editing/making false the "ratings" cookie used to fix this issue, but it didn't this time.

I can happily say though that just deleting it outright DID solve the issue.

EDIT: Never mind; it worked for ONE character sheet (the one I had open when I deleted the cookie) and doesn't seem to have worked for any others.

There is a semipermanent fix available here that will allow you to upvote as normal and not have to worry about the bug:

https://www.dndbeyond.com/forums/d-d-beyond-general/bugs-support/108539-portraits-not-loading?comment=133

Quote from IamSposta >>

There is a semipermanent fix available here that will allow you to upvote as normal and not have to worry about the bug:

https://www.dndbeyond.com/forums/d-d-beyond-general/bugs-support/108539-portraits-not-loading?comment=133

THIS! I followed the process in both my home and work PCs and keep cookie editor extension mentioned there on all the time. I do not suffer from this issue anymore on those browsers. Unfortunately this does not carry over to browsers that can't use that edit cookie extension, such as my phone's Chrome browser. I still get this issue when browsing dndbeyond using my phone.

I've griped about this issue forever it seems. I have an active ticket with the support desk since last fall that I've kinda just given up on following considering there is so much more complete information in that Portraits Not Loading thread and even in this thread and the dozens of others.

I've found this issue affects any images loading from dndbeyond, PDF downloads of character sheets form dndbeyond, the Insert Code function of the RTF editors used in different places all over dndbeyond, and the RTF editor entirely will fail to load if my dndbeyond site cookie is too big. I used to run into this issue constantly. 

Timeline of my frustrations:

• "Look, this is a problem." *chirp* *chirp*
• "Argh! here's a text dump of the issue, I found the problem!" *chirp* *chirp*
• "Here's some screenshots of what I'm talking about, please help me!" *chirp* *chirp*
• "Do you see all the bug posts complaining about this issue?" *chirp* *chirp*
• "Hey, I figured out a simple workaround that just involves a cookie editor extension, 3 clicks, and a hard refresh, but it works" *chirp* *chirp*
• some random programmer that contributes on the fan made browser extension, AboveVTT  "Try this extension to completely eliminate that thing causing the issue" OH HECK YEAH
• support ticket says something about looking at the timing of keeping persistent cookies. Really? It's been over 6 months and that's the response?

There's an extension that fixes it for you dndbeyond, I've given up on you fixing this.

I was just looking at the Ratings cookie, and it applies to the domain ".dndbeyond.com", not just "www.dndbeyond.com". So even if they are able to start serving up images from an "images.dndbeyond.com" subdomain, the Ratings cookie will still keep being sent with them. I'd say changing the Ratings cookie's domain is a very good starting point.