Input type = "file" - accept files without extension

Question

How can I accept files without any extension?
I need to accept .json and without extension files
I tried

<input type="file" accept=".json, . "/>  

and some of its variations with a dot and empty space, but none of them work

Answer 1

There is no such function in the HTML file yet. If you want, you can deploy this function either through server-side programming or through JavaScript validation. Accept all format files and confirm the format and find the desired formats and restrict all other formats.