FIX parser at has always been safe for your FIX messages. All parsing logic is done in your browser - it will work even if you disconnect your computer from the internet!
Yesterday the parser was updated to work over https. This was a preparatory step for the next giant leap in functionality. If you choose, you will be able to share FIX snippets with your colleagues or customers.
Soon you will be able to share FIX snippets securely and safely. Imagine sending this a simple link to a fix parser both of you already use, instead of pages of text badly formatted by outlook.
Coming (fairly) soon!