From doing a little research I can suggest doing a few things. Restarting Windows file explorer is my first suggestion. A lot of problems with the taskbar is caused by windows explorer. This can be done with the following steps:
# Open file explorer
# Hit Control+Alt+Delete and select '''Task Manager'''
# Navigate through the '''Processes''' tab of task manager until you find a process called '''Windows Explorer'''
# Right click on it and click '''Restart'''
# Wait a few moments and try Youtube, Netflix, or opening a photo after your taskbar reappears
My second recommendation is to restart your computer use Windows in “safe mode”. This mode boots Windows with only programs necessary for operation. A guide from Microsoft on how to do this can be found [https://support.microsoft.com/en-us/help/12376/windows-10-start-your-pc-in-safe-mode|here]. After booting into safe mode, then you can try to open a photo or watch Youtube/Netflix. Hopefully the first one works. If the second one helps let me know so that problem can be troubleshooted further.