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mfreedman3
Community Participant

Disappearing Graphics

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I have jpg images which display just fine, then for no apparent reason they disappear, only showing the file name.  Is this a bug? Am I doing something wrong?

279413_pastedImage_1.png

146 Replies

I have this problem all the time - doesn't matter how big or small the images are.  I had some images linked to pages on my home page, but I've changed them over to buttons because I was sick of seeing broken links all the time.  I have all my images stored in my course files.  I think this is a server issue on Instructure's side.  Are course files stored on Instructure servers?  The reason I think this is that I often have problems uploading files.  It will tell me to try again - so I do - and that works.  But if there are temporary glitches in uploading, couldn't there just as easily be temporary glitches in downloading?

We are having the same struggles. There was some discussion of this issue at Canvascon in Sydney recently, and the official Canvas commentary appeared to be 'isn't it great to see how the community helps each other to solve these problems'. It is hard to see this as a self help issue, when it feels as if it is actually a Canvas problem which has not been addressed.

mfreedman3
Community Participant

Please push this through your admins to open tickets. Then perhaps

aggregate the collective tickets here so we can see how many people are

dealing with this?

On Sun, Sep 16, 2018 at 10:33 PM s.carter@sydney.edu.au <

tom_gibbons
Community Contributor

So, I've seen this in a specific course, and I have some suspicions about why it may be happening in my instance.

How many of you who are having this experience are using a vanity URL? Like, we have canvas.unl.edu, as well as unl.instructure.com (we don't direct anyone to this one).

When you see the missing image, after the page has completed loading (some of the responses here say that the image may magically appear after a few seconds--that's network lag, not a resource location problem), right-click on the image placeholder and select "Inspect Element" (or whatever will bring up the HTML in your browser). Check to make sure that the top-level domain for both URLs in the image code match. In the image below, they do.

html with top-level domains highlighted

When I've seen problems is when they mismatch. I can't make a guess as to why there's a mismatch, but there can be.

The only solution I've seen for this is to delete the image and then place it again in the content (*Always use the content selector in Canvas to select the image from within your course files for best results*). If you have very involved styles applied to the image, this can be a real drag.

Because of some of the particulars of the course in question, it's difficult to kick this problem up the chain using a support ticket (institutional politics). BUT, it may be worth looking at examples in your course to see if there is a domain mismatch between the src and the api enpoint URLs. The super weird thing about this is, when you go to edit the content page (or whatever), the HTML doesn't show this mismatch. It's only when we're viewing the page with the broken image.

We are not able to consistently recreate the broken images. But when they occur, this seems to be the culprit.

jdick1
Community Participant

That's a really interesting observation about mismatched URLs. The next time I get a report of this happening from a teacher or a student, I will be sure to check this.

I wanted to point out that my primary institution has a vanity URL and we had experienced this before and submitted a support case that got a resolution. Every now and then we still experience it so it's still a here today, gone tomorrow issue. I also teach part time for another institution and it happens on their non-vanity URL. More than 3 times I've had to correct the home page image on a course that was designed for me by an instructional design team.

Conclusion: This seems as mysterious an issue as ever. I would love for someone from Instructure to take a look at this thread and jump in here to discuss what causes this to happen and what the course of resolution might be. The original question is 'answered' so I doubt that it would get the attention of such an individual. 

tom_gibbons
Community Contributor

The mismatch that I'm seeing is that the api-endpoint URL is pointing back to a course developer's instance of Canvas. My thought process went something like: it doesn't sound like most people are seeing this with courses that were developed in other instances of Canvas. I wonder if it might also be something with the vanity URL.

But now that I'm thinking about it, I'm wondering if this is happening with courses developed at other places and are imported into other instances of Canvas. Or that are pushed into .imscc files and reimported. Or something. I mean, it's obviously not consistent, but maybe there's another confounding factor, as well.

hrm.

In the ~20 minute phone call regarding case 03578688 (as just one example from our institution), this faculty member reported numerous questions in several quizzes in a few different courses.  There are many specific examples being reported to Instructure Support.  I think  @mfreedman3 ‌ is just trying to illustrate that there are numerous reports of these problems coming in over the last several months.  Until Instructure support seems to realize that there is a larger problem, bringing attention to the many examples here in the community is helpful to hopefully change the mindset of the support agent from troubleshooting these as isolated incidents to realizing that there is an underlying systemic problem.  Yes, specific details help, but those specific details alone don't change the support agent's mindset beyond those specific case details to viewing this as a larger, widespread problem.  The numerous isolated cases need to be tagged by Support under a common Jira so that they can be collected, analyzed, and properly resolved rather than every single open support case being viewed as an independent and isolated problem blamed on improper caching or other such nonsense.  I understand that each support agent needs to start somewhere, and browser issues are a great place to start with individual, isolated problems.  However, starting there is a sure sign that this particular issue still isn't being viewed as anything more than individual, isolated problems.  If the support agent started with a Jira about a wide-spread issue (which this clearly is as supported by so many different threads here in the community), people would likely be less frustrated by the "clear your cache" solutions being offered.

John_Lowe
Community Champion

The problem with that solution is that it assumes all of your users are accessing Canvas from the same location.  That may be true in K-12, but it is certainly not true in Higher Ed.  We cannot expect users around the globe to speak with their Internet service providers to whitelist specific Instructure resources.

mfreedman3
Community Participant

The net result of my ticket and this thread so far:

- Instructure support does not monitor these threads, so we are only

increasing our awareness in the community, not Instructure's.

- Instructure recognized the problem and released a fix a few months ago.

Based on the comments here, the problem continues.

- Instructure asked that we all report these instances through our admins

so that our actions fit their process. I have not seen reports of any other

tickets posted in this thread.

I am not aware that Instructure considers this an open issue. If other

users post their ticket #'s here, perhaps we could be a big picture view.

If this does look widespread, we could then refer this data to our account

team for escalation.

Michael