Wizcorp Blog [Fix inside] Why Windows Explorer goes funky in folders with TypeScript files

If you're doing TypeScript development on Windows, you may have noticed that some folders hang the file explorer, as shown below.This can be annoying, because if you have a slower machine and there are a lot of files in a given folder, the Explorer may hang out for several seconds when you visit it for the first time.So why is Windows starting to show the folder as usual, blocking a second on every file, and then deciding to switch the view to thumbnails ?A little explanation on how the Explorer works internally is in order here.The file explorer has several so-called "kinds" of folders, which configure how files are shown by default. You can override, for each of these kinds, which layout you want. By default since Windows 7, general items use the "Details" view as shown above, while Pictures and Videos show in "Big thumbnails", and Music a variation of the "Details" layout with ID tags.The kind of folder is auto-determined based on its contents. For optimization purposes, Windows tries to delay determining the appropriate kind for a folder until you open it for the first time.So, in our situation, for some reason Windows, after some trouble, determines that this folder contains Videos.Which is technically true. Because .ts files, before being TypeScript files are actually Transscript files, used on DVDs, and supported natively by Windows. Although they look like valid video files, they are not, so as the file handler goes and tries to parse it, it hangs for a while, which causes the delay. Nevertheless, the folder is determined as being a video folder because it contains a majority of those.The solution then?If you are annoyed here is a completely safe operation to do. Open the registry editor, navigate to Computer\HKEY_CLASSES_ROOT\.ts (tip: as you open regedit.exe, type Ctrl+L to focus the address bar, paste the path and then press enter), double click on the PerceivedType key and replace video by text.This will stop the madness for future folders. You then may want go ahead and define another default program for those files, such as Sublime Text. You may also dig further down and replace the Content type and the (Default) keys to read text/plain and txtfile respectively for example. Look at the .txt key just below to see how a simple text file is configured on Windows.Avoid touching anything else before prior research. In case you have messed things up, you may get a backup of the original, unmodified .ts key here. Download it, add the .reg extension by renaming the file and double-click to run it.Note: in case some folder remain shown as videos, you can reset the Windows Explorer by doing a Disk Cleanup (My Computer -> Right click on <My Drive (C:)> -> Disk Cleanup -> make sure that Thumbnails is ticked and click OK.