can anyone help with snappymail ?

I've been using rainloop (webmail client), but it's not being updated,
and there's a fork, called snappymail.  Both are in the freebsd ports
and packages.  Neither have a maintainer.

I've installed snappymail-php84 as a pkg.  I try to use the /?admin url 
to do the setup, and get this error message:

-------------------------------
[302] The following PHP extensions are not available in your PHP 
configuration!

     mbstring
     li>
     fileinfo
-------------------------------

I think we can ignore the spurious "li>".  Both mbstring and fileinfo 
php extensions are installed (and were installed by pkg when snappymail 
was installed).  They are listed in the output of "php -m".  The actual 
.so files are where they should be (along with all the other php 
extensions, permissions are the same, etc.

I'm not a PHP guy, so I'm using google to learn about things like "php -m".

This is a 14.3-RELEASE-p14 system.

How can I find out why snappymail is complaining about these extensions 
being missing (and fix it) ?

Thanks,
Bill Dudley