New server, new PHP version, same old gui

In other news: After the previous server had its PHP updated the site broke. It only took 3 years, but I have finally gotten around to updating the source code to be PHP7 compliant. At the request of veteran BSG-gamers I have also added https - it is 2021 after all. I have tested the new setup and fixed the bugs i could find. If you discover something that isn't wokring be sure to let me know.

Fatal error: Uncaught TypeError: Unsupported operand types: string + string in /mnt/HC_Volume_100699292/websites/BSG/includes/theme_functions_include.php:135 Stack trace: #0 /mnt/HC_Volume_100699292/websites/BSG/themes/Gillette/theme.php(152): newsopts() #1 /mnt/HC_Volume_100699292/websites/BSG/news.php(87): render_news() #2 {main} thrown in /mnt/HC_Volume_100699292/websites/BSG/includes/theme_functions_include.php on line 135