I have installed the cucumber-java and gherkin plugins in IntelliJ IDEA but when I create a .feature file it is not recognized as a feature file. I did restart IntelliJ and
Check File -> Settings -> Editor -> File Types and click on the Text file type. Look at the Registered Patterns section below and verify that the file you're trying to create is not in the list of recognized patterns for Text file types.
This might happen if you created the file without initially giving it the .feature extension. If you do that and then try to add the extension afterwards IntelliJ will probably still think it's a text file and will not treat it as a feature file. This was the fix for me.
If you're seeing IntelliJ recognizing your intended feature file as some other type of file then check the recognized patterns for that file type and verify again that the file you're trying to create is NOT in that list.
See http://www.gisremotesensing.com/2014/11/solution-intellij-not-recognizing.html
For some setups, this is only half the story. Once, you have removed the old file type; now follow the steps:
Now you are all set. The feature files will be back to normal.