I get the following error when I click the Global News link in the Dashboard drop-down menu:

Fatal error: Call to undefined function is_site_admin() in /home/monthofg/public_html/wp-content/plugins/threewp-global-news/ThreeWP_Base_Global_News.php on line 179

I installed this plugin and wrote my first global message, which seemed to work fine, but I just tried to write a second and it doesn’t want to work. I click the “Add News” link, type in my title and text, and choose who it should be viewable to, click “save”, get the “News item created!” message in the yellow box, but my message isn’t shown to anyone (I’ve logged in as a test user to check), and isn’t in the lists of messages to view/edit. I don’t see it anywhere :/

https://www.ads-software.com/extend/plugins/threewp-global-news/