system information

• Steam client version: latest
• Distribution (e.g. Ubuntu): ubuntu/windows
• Opted into Steam client beta?: no
• Have you checked for system updates?: yes

Please describe your issue in as much detail as possible:

Dota 2 redownload files each time i change my OS.
it happend to other people also as someone asked it here
Needs to tell Dota 2 is stored on a NTFS partition and both steam clients redirect to same Steam Library folder to avoid downloading games multiple times.
Also keep in mind it wasn't a case before. I was playing before without any issue.

Steps for reproducing this issue:

1. Download Latest dota 2 update in windows or linux. then everything is fine
2. Switch OS to play on windows (if i were on linux or vice versa)
3. Dota 2 needs to (re)download about 800 mb each time.
4. Going to step 1 again.