A new feature in Moodle 3.5 is Dashboard images.
(If you’re not familiar with the term Moodle Dashboard it might be because you are using an older version of Moodle as this location was previously called Home, or My Home).
If course images have been added in the course settings, they will display in the dashboard. Where no images have been added, coloured patterns appear.
This feature was a surprise for many people after upgrading to Moodle 3.5, with randomly coloured areas suddenly appearing !
This might force administrators (or maybe the course teachers?) to quickly find some suitable images. It may be better for administrators or designers to do this, to maintain a standard and coherant appearance.
You can see this feature in operation on our https://www.moodlebites.com site.
There in no specific guidance on the size of images to use in Moodle Docs. However, it’s clear that the images should be landscape format. Using images that are too small results in the being streched and losing resolution. Using images that are too big results in them being cropped, which cam produce unexpected results. we have found using 800×400 works quite well across the browser, Moodle Desktop, and Moodle App.
As well as the images looking good on a desktop/laptop when viewing via a web browser, the Dashboard images work really well when using the Moodle App on a tablet or smartphone.
There is currently a developing discussion relating to whether administrators should be able to turn this feature off if they wish. This would be a great idea, because randomly coloured blocks of colour do not add anything useful to the experience of using Moodle, and take up space at the top of the page, which is a definite factor to consider when using the more limited space in the Moodle App.