Trying to get property 'identifier' of non-object

Sun, 24 May 2020 10:23:37 +0000
Message: Trying to get property 'identifier' of non-object
PHP version: 7.4.6
WoltLab Suite version: 5.2.6
Request URI: /forum/board-feed/13/
Referrer:
User Agent: Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.92 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)
Peak Memory Usage: 7312504/536870912
======
Error Class: wcf\system\exception\ErrorException
Error Message: Trying to get property 'identifier' of non-object
Error Code: 0
File: /var/www/vhosts/android-freaks.de/httpdocs/lib/system/WCF.class.php (341)
Extra Information: -
Stack Trace: [{"file":"\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/lib\/system\/event\/listener\/hideForGuestsLinkListener.class.php","line":27,"function":"handleError","class":"wcf\\system\\WCF","type":"::","args":[]},{"file":"\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/lib\/system\/event\/EventHandler.class.php","line":221,"function":"execute","class":"wcf\\system\\event\\listener\\hideForGuestsLinkListener","type":"->","args":[]},{"file":"\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/lib\/system\/html\/output\/node\/HtmlOutputNodeProcessor.class.php","line":83,"function":"fireAction","class":"wcf\\system\\event\\EventHandler","type":"->","args":[]},{"file":"\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/lib\/system\/html\/output\/HtmlOutputProcessor.class.php","line":66,"function":"process","class":"wcf\\system\\html\\output\\node\\HtmlOutputNodeProcessor","type":"->","args":[]},{"file":"\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/forum\/lib\/data\/post\/Post.class.php","line":116,"function":"process","class":"wcf\\system\\html\\output\\HtmlOutputProcessor","type":"->","args":[]},{"file":"\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/forum\/lib\/data\/thread\/FeedThread.class.php","line":58,"function":"getSimplifiedFormattedMessage","class":"wbb\\data\\post\\Post","type":"->","args":[]},{"file":"\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/forum\/lib\/data\/thread\/FeedThread.class.php","line":72,"function":"getSimplifiedFormattedMessage","class":"wbb\\data\\thread\\FeedThread","type":"->","args":[]},{"file":"\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/templates\/compiled\/28_wcf_1_rssFeed.php","line":50,"function":"getExcerpt","class":"wbb\\data\\thread\\FeedThread","type":"->","args":[]},{"file":"\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/lib\/system\/template\/TemplateEngine.class.php","line":334,"args":["\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/templates\/compiled\/28_wcf_1_rssFeed.php"],"function":"include","class":"","type":""},{"file":"\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/lib\/page\/AbstractFeedPage.class.php","line":90,"function":"display","class":"wcf\\system\\template\\TemplateEngine","type":"->","args":[]},{"file":"\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/lib\/page\/AbstractPage.class.php","line":114,"function":"show","class":"wcf\\page\\AbstractFeedPage","type":"->","args":[]},{"file":"\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/lib\/system\/request\/Request.class.php","line":83,"function":"__run","class":"wcf\\page\\AbstractPage","type":"->","args":[]},{"file":"\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/lib\/system\/request\/RequestHandler.class.php","line":107,"function":"execute","class":"wcf\\system\\request\\Request","type":"->","args":[]},{"file":"\/var\/www\/vhosts\/android-freaks.de\/httpdocs\/forum\/index.php","line":9,"function":"handle","class":"wcf\\system\\request\\RequestHandler","type":"->","args":[]}]