"Import" missing in PoE2 filter syntax.

Loot filters for PoE 1 include "Import" to import an existing loot filter into the file. This also includes an "optional" keyword to allow for the import to be ignored (and not error) if the file doesn't exist.

So the following syntax would be correct in a PoE 1 filter:
Import "MyOptionalRules.filter" Optional

While this is valid for PoE 1, this doesn't seem to been included for PoE 2 loot filters. I'm therefore including this issue/request here as I don't know if it's just a case of it being a bug in the lootfilter code being added to PoE 2, or if it's just not been finished yet.

Personally I find the import feature so valuable for use in loot filters, as it allows to me create one base.filter for how I enjoy things to be displayed in game, and then for specific builds I can then just create a new filter to hide the things I don't care about for that build, as well as highlighting build specific items ending with the Import command to import my base.filter for the rest.

I have tested this on the website filters edited page, to check the syntax - which shows that this is still valid for PoE 1 filters, but the page highlights the use of "import" as being a syntax error when used for PoE 2.