Unrecognized format error

[BarryJohnson01]

I have installed and configured the fcm-push module. I use firebase on a number of websites with the same credentials.
What I notice is that the browser doesn't asks for permissions, which it does for the other websites. So I assume the module is not working. I checked the log and found the following error.
By the way... it would be nice to see some kind of test result, or a test button to check the API connection.

Error message in HumHub log:
yii\base\InvalidParamException: Unrecognized format '' in /var/www/vhosts/lostboysworld.org/protected/vendor/yiisoft/yii2-httpclient/src/Client.php:178
Stack trace:
#0 /var/www/vhosts/lostboysworld.org/protected/vendor/yiisoft/yii2-httpclient/src/Response.php(199): yii\httpclient\Client->getParser(NULL)
#1 /var/www/vhosts/lostboysworld.org/protected/vendor/yiisoft/yii2-httpclient/src/Response.php(33): yii\httpclient\Response->getParser()
#2 /var/www/vhosts/lostboysworld.org/protected/vendor/yiisoft/yii2/base/Component.php(140): yii\httpclient\Response->getData()
#3 /var/www/vhosts/lostboysworld.org/protected/modules/fcm-push/components/FcmApi.php(69): yii\base\Component->__get('data')
#4 /var/www/vhosts/lostboysworld.org/protected/modules/fcm-push/components/NotificationTargetProvider.php(32): humhub\modules\fcmPush\components\FcmApi->sendNotification(Object(humhub\modules\user\notifications\Followed), Object(humhub\modules\user\models\User))
#5 /var/www/vhosts/lostboysworld.org/protected/humhub/modules/notification/targets/MobileTarget.php(56): humhub\modules\fcmPush\components\NotificationTargetProvider->handle(Object(humhub\modules\user\notifications\Followed), Object(humhub\modules\user\models\User))
#6 /var/www/vhosts/lostboysworld.org/protected/humhub/modules/notification/targets/BaseTarget.php(161): humhub\modules\notification\targets\MobileTarget->handle(Object(humhub\modules\user\notifications\Followed), Object(humhub\modules\user\models\User))
#7 /var/www/vhosts/lostboysworld.org/protected/humhub/modules/notification/components/NotificationManager.php(89): humhub\modules\notification\targets\BaseTarget->send(Object(humhub\modules\user\notifications\Followed), Object(humhub\modules\user\models\User))
#8 /var/www/vhosts/lostboysworld.org/protected/humhub/modules/notification/components/NotificationManager.php(108): humhub\modules\notification\components\NotificationManager->sendBulk(Object(humhub\modules\user\notifications\Followed), Object(humhub\modules\user\components\ActiveQueryUser))
#9 /var/www/vhosts/lostboysworld.org/protected/humhub/modules/notification/jobs/SendNotification.php(41): humhub\modules\notification\components\NotificationManager->send(Object(humhub\modules\user\notifications\Followed), Object(humhub\modules\user\models\User))
#10 /var/www/vhosts/lostboysworld.org/protected/humhub/modules/queue/ActiveJob.php(33): humhub\modules\notification\jobs\SendNotification->run()
#11 /var/www/vhosts/lostboysworld.org/protected/vendor/yiisoft/yii2-queue/src/Queue.php(246): humhub\modules\queue\ActiveJob->execute(Object(humhub\modules\queue\driver\MySQL))
#12 /var/www/vhosts/lostboysworld.org/protected/vendor/yiisoft/yii2-queue/src/cli/Queue.php(162): yii\queue\Queue->handleMessage('473', 'O:49:"humhub\mo...', '300', '1')
#13 /var/www/vhosts/lostboysworld.org/protected/vendor/yiisoft/yii2-queue/src/cli/Command.php(146): yii\queue\cli\Queue->execute('473', 'O:49:"humhub\mo...', '300', '1', '36931')
#14 [internal function]: yii\queue\cli\Command->actionExec('473', '300', '1', '36931')
#15 /var/www/vhosts/lostboysworld.org/protected/vendor/yiisoft/yii2/base/InlineAction.php(57): call_user_func_array(Array, Array)
#16 /var/www/vhosts/lostboysworld.org/protected/vendor/yiisoft/yii2/base/Controller.php(181): yii\base\InlineAction->runWithParams(Array)
#17 /var/www/vhosts/lostboysworld.org/protected/vendor/yiisoft/yii2/console/Controller.php(184): yii\base\Controller->runAction('exec', Array)
#18 /var/www/vhosts/lostboysworld.org/protected/vendor/yiisoft/yii2/base/Module.php(534): yii\console\Controller->runAction('exec', Array)
#19 /var/www/vhosts/lostboysworld.org/protected/vendor/yiisoft/yii2/console/Application.php(181): yii\base\Module->runAction('queue/exec', Array)
#20 /var/www/vhosts/lostboysworld.org/protected/vendor/yiisoft/yii2/console/Application.php(148): yii\console\Application->runAction('queue/exec', Array)
#21 /var/www/vhosts/lostboysworld.org/protected/vendor/yiisoft/yii2/base/Application.php(392): yii\console\Application->handleRequest(Object(yii\console\Request))
#22 /var/www/vhosts/lostboysworld.org/protected/yii(29): yii\base\Application->run()
#23 {main}

[marc-farre]

It means that your Server Key is not correct.
I should start with AAAA as you can see on this screenshot (on the bottom right, the token column):