EPD - Online Learning Systems - Moodle Browser Security Changes
Issue: The Course Links Block Cannot be Seen
If there are problems viewing the Course Links block in UW-Madison Moodle courses, use one of the following suggestions to resolve the issue.
Reason: Mixed Content Block
What is Mixed Content? When a user visits a page served over HTTP, the connection is open for eavesdropping and man-in-the-middle (MITM) attacks. When a user visits a page served over HTTPS, the connection with the web server is authenticated and encrypted with SSL and hence safeguarded from eavesdroppers in MITM attacks.
However, if an HTTPS page includes HTTP content, the HTTP portion can be read or modified by attackers, even though the main page is served HTTPS. When an HTTPS page has HTTP content, the content is "mixed." The webpage that the user is visiting is only partially encrypted since some of the content is retrieved encrypted of HTTP. The Mixed Content Blocker blocks certain HTTP requests on HTTPS pages.
Solution 1: General
An easy way to resolve the issue is switching to another browser. Some versions of browsers (Internet Explorer 10, Firefox 23.x) have mixed Content Blocker enabled by default Chrome, Safari, Opera, or other reliable browsers may be considered to open the course pages.
Solution 2: Internet Explorer 10
In Internet Explorer 10, the default setting for displaying mixed content is Prompt. So when the page is loaded, a dialog box will pop up and ask to "Show all content." The message only lasts for 5 seconds, but it can always be reloaded to bring it back.
To always display mixed content, follow the steps below.
1. Go to Gear icon → Internet Options.
2. Select the Security tab.
3. Click on the Internet Zone icon at the top of the tab page.
4. Click Custom Level.
5. In the "Miscellaneous" section change "Display mixed content" from Prompt (default) to Enable.
6. Repeat steps 1-5 for the Local intranet and Trusted sites zones.
Solution 3: Firefox 23
In Firefox 23+, Mixed Active Content is blocked by default, but if the shield icon beside the location bar is clicked, the protection on the page can be disabled.
The Mixed Content Blocker can be permanently configured by:
- Opening a new tab in Firefox.
- Entering "about:config" in the location bar to initiate configuration window.
- Finding "security.mixed_content.block_active_content" setting.
- Double clicking on the value to switch to "false."
Should there be any further questions regarding this issue, please contact technical support: firstname.lastname@example.org.