Vlad Not a problem, I have created instructions to recreate the issue!
Go to https://canvas.instructure.com/login/canvas and select “Browse courses” on the top right, this should take you to the homepage and give you a few sample courses to pick from. To recreate the issue, go to the course called “Spreadsheet Automation” and then click on “Files”, click on “Class Examples” and it should take you to a folder containing a variety of files, click on, for example, “census_520.xls” which is the topmost file, do not download it, just click on it. The automatic refreshing should occur immediately. This is the case for most file previews such as .pdf files and .docx files (examples of .docx files can be found on the homepage under the course called “Video Mystery Shopping” and going into the “Files”). This issue makes it very hard to use canvas as many assignments require the use of file previews, and this constant refreshing makes it impossible to view any pages with previews.