Tracking causes that make screenshots flaky

[isoos]

• non-local images may be flaky to load (e.g. fake profile picture, should be replaced by a fixed image)
• search field screenshot may or may not have the cursor blinking (may be fixable with static cursor in integration tests)
• Material components rendering is often flaky (checkboxes and dropdowns mostly, sometimes only a few pixels, sometimes the full component)
• sometimes the animation are done, sometimes missing (folding sections' icon animation)
• sometimes the hover effect on icons is triggered (may be fixable with forcing the focus to a specific element)