VSCode open a new file in preview mode by default.
When you open a file, and then, open another file. The former file will be OVERRIDE!
Very Annoying!
How to determine if a file is preview mode? See the file name⬇️

The name344_reverserString.js is Italic so that it is under preview mode
Changing ways:
Enable Preview in Settings![[外链图片转存失败,源站可能有防盗链机制,建议将图片保存下来直接上传(img-WyG5Kx8n-1627386130229)(How%20To%20Always%20Open%20a%20File%20in%20VSCode.assets/image-20210727194025931.png)]](https://1000bd.com/contentImg/2023/11/08/040940156.png)
Reference
https://stackoverflow.com/questions/38713405/open-files-always-in-a-new-tab