If you’ve ever clicked on a screenshot in the WordPress plugin directory and received a download prompt, you’re not the only one. In fact, it’s a widespread issue that affects a number of plugins. Screenshots are important as they help with troubleshooting, previewing features, and give users a sense of what to expect when it’s activated. But if you can’t see important details, they’re a moot point.

Mika Epstein, who reviews plugins before they’re added to the directory, wrote about the issue in early 2014. The prompt appears for images that use the incorrect MIME Type. Otto explains how to set the correct MIME Type using TortiseSVN on Windows or where to look if you use a different SVN client.
On Windows, using TortoiseSVN, you can right click the screenshot file, and select the TortoiseSVN->Properties menu. There you will find the svn:mime-type property, probably incorrectly set to “application/octet-stream”. Change that to the proper mime type of “image/png” or “image/jpg” accordingly. Afterwards, commit the change.
If you prefer command line SVN:
svn propset svn:mime-type image/png screenshot-1.png
svn commit
Or similar. If somebody uses a different SVN client, look for “properties” and then the svn:mime-type property.
Once the changes are made, upload them to the plugin directory. They’ll take effect once the directory is synchronized. It’s a simple change that vastly improves the effectiveness and user experience of viewing screenshots.
13 responses to “Plugin Authors: How to Avoid Download Prompts Associated with Screenshots on the WordPress Plugin Directory”
I thought it was builded like that. I don’t even remember if at least once any screenshot was opened instead of downloaded using any browser.
Click on any of the screenshots for Woocommerce in FireFox and you’ll see the download prompt. https://wordpress.org/plugins/woocommerce/screenshots/
Thanks for the reminder Jeff – we’re fixing this up! :)
What an awesome tip, just checked my new plugin’s screenshots and sure enough I got the download prompts. Didn’t even know it was doing that. Thanks!
Now it would be nice if those images opened in some kind of Modal instead of on a new blank screen…
Oh, I see I cannot edit my comment anymore? Ah well, an addition then.
If you’re using Cornerstone (I believe Mac only?) to commit your plugins, then you can go to Get Info (CMD + I) and then switch to the tab Properties, where you can change the MIME Type with a dropdown.
Sometimes they do. But unfortunately it’s not very often …
otto was a great help with this when we were looking into it a couple weeks ago. see: https://twitter.com/Otto42/status/550122425464004608 and https://twitter.com/Otto42/status/550122819170729984
perhaps a simple script could be written for changing the MIME type? that could be super helpful for future plugin developers.
That would be an ideal solution. Sometimes I forget to change the mime type of my screenshots. It’s not that it’s difficult, it’s just an extra step we have to remember we pushing to the repo.
Definitely a great reminder. Thanks! Now to remember to do it and keep track of it as well.
This has been driving me mad for about a year now. I’ve cross referenced readme.txt files and image extensions but couldn’t see why my screenshots were downloading while others opened in a new tab. And here’s the answer, finally :) Thanks Jeff!
You’re welcome, glad it helped you!
Anyone knows how to do this in SmartSVN, properties mime type is grayed out on image.