Bitbucket doesn't show source file contents in text but view raw

My source code extension is .mq4 which is written by mt4 script language. When creating repository, the language I leave it blank, because there is no file type supporting it.

After pushing files to the repository, this type of files are not able to be viewed. But I see "View Raw" instead. clicking the view raw link it downloads the file instead of showing it in editor.

I've tried to recreate a clean repository but no luck.

the source code is pure text file that can be opened by any text editors. I attached a sample file for your info.