@Mauricio Meza. Are you using the setting "Store as image file"? Enable that setting and try again. It won't fix images that are already made, but it might fix future images.

@Mauricia Meza The reason is that Moodle sometimes strips images that are inline base64 encoded. I plan on making the setting ON by default in future versions.

I did, but student made the drawing and "Insert Sketch" button doesnt work

So, it wont work in students answers?

If using "Store as image file" it will work because it is literally adding the image just like Moodle adds any other image. However, student sketches made before the setting change still might not work. There is a workaround, by changing a weblib.php file. Go to lib/weblib.php:

Look for

$config->set('URI.AllowedSchemes', array(
under it you will see a bunch of array values set to true. Add the following to the top of the array()

'data' => true,

The problem was solved.
Used "task" plugin and not the "lesson" because with this it does not work.
Thank you so much.
Excellent plugin

I have the same issue, I cannot see student's answer in sketch (but teacher can do that without any issue). Tried to turn on "Store as image file", but the "insert sketch" button become unresponsive. Could you please help? Thank you.

@Esther Can you tell me what version of the plugin you are running. What version of Moodle. And what browser you are using?

We are trying to find a way to have a background image for students to respond by writing over the top of. (graphing a line on a coordinate plane) Whenever we link an image in the response template, the "insert sketch" button no longer functions. We are using Moodle version 3.8 in Chrome.

@Micah Degner In my experience, selecting an image in TinyMCE isn't always the easiest. I've found right clicking on an image and then opening the editor works. Just tested the latest version in Chrome with the TinyMCE editor. I did however see an issue where the screen scrolls or shifts in a way that the top menu becomes hidden. When I have some time I'll look at this again.

@Matthew Davidson Where we are having the issue is not with students adding an image in the editor, but in submitting responses when there is a pre-loaded image that we have added in the response template from Moodle... When students click "insert sketch" nothing happens. If students add the image themselves in the editor, then it works. But not if we have the image automatically loaded in the response template. Thanks!! Micah

@Micah Degner I'm assuming you are talking about using Sketch in a quiz essay question. So the issue is that Moodle only allows you to link images and not save images to a local storage in the response template. So most modern browsers will prevent that image from running through certain functions because of cross-origin issues. if you look in the browser console you will see an error when you click the "Insert Sketch" button that speaks to this. The solution is to make sure your grid image is local. So my workaround is to create a Page in moodle. Make this page hidden but available to students. Add any images you might want to use on that page. Save it, and then right click and copy the image location url from that Page. Make sure the image url looks like ".../pluginfile.php/1234567890/mod_page/content/1/someimage.jpg" and not ".../draftfile.php/...". Then use this URL in the response template. Since it is local to your server, it should work.

@Matthew Davidson THANK YOU!!! This worked exactly how we want it to. The timely response is much appreciated.

@Micah Degner I have just made commits to both the tinymce and atto branch (see https://github.com/Syxton/atto_sketch/commits/master) that may fix this issue.