Problem with pagination

Hi,

the moment I activate the “Future” plugin the pagination is broken. The links of the page-numbers [1] [2] [3] … look like this:
https://www.dav-duesseldorf.de/page/2www.dav-duesseldorf.de/page/2/?future=

It stops when I comment out line 417:
add_filter('paginate_links','futurems_paginate_links');

Parameters to function futurems_paginate_links in line 406:

$link: string(47) "http://wordpresstest.dav-duesseldorf.de/page/1/"
$future: NULL

Returns:
$link: string(94) "http://wordpresstest.dav-duesseldorf.de/page/1wordpresstest.dav-duesseldorf.de/page/1/?future="

Please help 🙂

Best regards,
Sebastian

https://ww.wp.xz.cn/plugins/future/