Usually in Chrome, when something works correctly in Incognito Mode, it is usually the fault of some extension.
By default, extensions are only active in normal windows. Very often, extensions can cause problems when viewing webpages or webpage content.
Usually, extensions are all disabled for Incognito windows so it is a fairly good testing mode.
You can find which of your extensions is causing the problem. Go to chrome://extensions and first disable all your extensions and re-test. Viewing webpages in a normal window should be fine after that. Then re-enable your extensions one-by-one to see which one was causing that error.