As you have noticed, some times the forum breaks when people post shit, its actually due to a old plugin which managed spoilers, which has now been replaced.
If you have spoilers, you will need to change it to match the new syntax or click the eye icon in the editor.
Please make sure you are posting the correct markdown syntax and check your post before posting to stop shit breaking.
PS. At the moment, images do not work within the spoiler tags, but feel free to post images in a post. The new forum software does not load the image until to scroll to it (lazyloading), which keeps the website rendering times down and stops slowing the website down.