Command line argument preserve comments doesn't work

[puranjayjain]

Using the command below

java -jar compiler/closure-stylesheets.jar --pretty-print --preserve-comments --allowed-non-standard-function -webkit-transform --allow-unrecognized-functions --allow-unrecognized-properties --output-file closure/closure.css --output-renaming-map-format CLOSURE_COMPILED --rename CLOSURE --output-renaming-map closure/renaming_map.js closure/concated.css

I expect the output should be pretty printed but also have comments, but they are rather stripped, is there something I'm doing wrong? are only certain types of comments supported?

[iflan]

I haven't had time to verify this, but I will try soon. Do you have a particular input file that you can share?

[puranjayjain]

Its a css file I have renamed it to a .txt file as github doesnt support that file type.
material.txt

Although, it's minified in its current state but I have tried to use the above option on an unminified file as well.