How to create custom workshop thumbnails:
1. Create the thumbnail (must be <1 MB in size)
2. Create a txt file, then rename it to have a `.vdf` extension and open it with notepad. On that file write this, replacing `workshopid` with the id of the blueprint you want to update (the number at the end of the workshop link after `?id=`) and `C:\\path\\to\\thumbnail.png` with the path to your thumbnail file (using `\\` as folder separators)
```
"workshopitem"
{
"appid" "585420"
"publishedfileid" "workshopid"
"previewfile" "C:\\path\\to\\thumbnail.png"
}
```
3. Download [steamcmd](<https://developer.valvesoftware.com/wiki/SteamCMD#Downloading_SteamCMD>) (a command line version of the steam client made by valve) and extract it into a folder
4. Go to that folder with cmd and run it (just type `steamcmd` while on the same folder), this will update it and start it.
5. Type `login username password steamGuardCode` (if you don't use steam guard 2FA you can skip that). This might log you out of the normal steam client
6. Type `workshop_build_item "C:\\path\\to\\file.vdf"`, replacing `C:\\path\\to\\file.vdf` with the path to the txt file
7. Quit the program by typing `quit`

## Troubleshooting

### ERROR! Failed to load build config file

The program can't find your txt file. Make sure you wrote the file path in the command correctly, using `\\` as folder separator and inside of quotes

Make sure you correctly changed the file extension of the txt file. By default, windows hides file extensions, and you can't change it without enabling them. If when you create a new txt file you don't see the name end in `.txt`, you need to enable the file extensions under the view menu at the top bar of the file explorer, then change the extension of the file again

### ERROR! Failed to parse build config file

The program couldn't process your txt file correctly. This can be caused by many things, make sure its content are exactly as described with only the modifications mentioned

What is the ideal resolution for a thumbnail?