html5画布代码适用于w3schools的tryit编辑器或jsfiddle，但不能保存为html文件

so basically in the Tryit Editor from the w3schools website my code written here works 100% perfectly fine. although I will mention when its first loaded in the editor the wall sprite does not appear drawn but when i click run a second time it does draw. the same exact thing happens in jsfiddle. the problem is when i copy the code to notepad and save it as an html file it just will not draw the wall anymore. I tried changing the source of the image countless times, it just doesnt make sense why it wouldn't work. I have searched the internet for the same problem as well as stackoverflow, but ive only found problems with jsfiddle where someone has forgotten that it automatically adds tedious aspects and formatting thats required.so basically in the Tryit Editor from the w3sch