I have recently started receiving reports of an issue where a user logs into Moodle and their page renders as plain HTML with no CSS formatting or JavaScript functionality. We updated to Moodle version 3.1.1 and the latest version of the Essential theme at the end of August, but did not start receiving reports of this issue until several weeks after the updates were complete. I cannot seem to find a pattern as to what causes this issue: it happens intermittently, to people of various roles on the Moodle site, on different operating systems, in different browsers (Chrome, Firefox, Safari, Edge), and I cannot replicate it without waiting for someone to come in with the issue.
Here is what I have been able to deduce so far:
1. This is happening because the browser is trying to load the Moodle landing page using HTTPS rather than HTTP, but the stylesheet and script resources are still being loaded using HTTP.
2. The login page sends the user to the Moodle landing page using HTTP, but the browser receives a 301 message from the server telling it to use HTTPS to load the page.
3. Clearing the browser's cache will temporarily fix the problem.
Has anyone dealt with this issue, or have an idea as to why it may be happening?
Thanks in advance.
Joshua Wilcox