[TASK] Update typo3 version requirement

composer.json

@@ -16,7 +16,7 @@
 		}
 	],
 	"require": {
-		"typo3/cms-core": "^7.6"
+		"typo3/cms-core": "7.6.0 - 8.7.99"
 	},
 	"suggest": {
 		"sgalinski/sg-comments": "Flexible comments system",

ext_emconf.php

@@ -22,7 +22,7 @@ $EM_CONF[$_EXTKEY] = [
 	'version' => '3.7.1',
 	'constraints' => [
 		'depends' => [
-			'typo3' => '7.6.0-7.6.99',
+			'typo3' => '7.6.0-8.7.99',
 			'php' => '5.5.0-7.0.99',
 		],
 		'conflicts' => [],