[21:58:18 ERROR]: [PlaceholderAPI] Failed to load class files of expansion.
java.util.concurrent.CompletionException: java.lang.UnsupportedClassVersionError: at/helpch/placeholderapi/expansion/server/ServerExpansion has been compiled by a more recent version of the Java Runtime (class file version 61.0), this version of the Java Runtime only recognizes class file versions up to 52.0
        at java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:273) ~[?:1.8.0_312]
        at java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:280) ~[?:1.8.0_312]
        at java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1606) ~[?:1.8.0_312]
        at java.util.concurrent.CompletableFuture$AsyncSupply.exec(CompletableFuture.java:1596) ~[?:1.8.0_312]
        at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289) ~[?:1.8.0_312]
        at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056) ~[?:1.8.0_312]
        at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692) ~[?:1.8.0_312]
        at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:175) ~[?:1.8.0_312]
Caused by: java.lang.UnsupportedClassVersionError: at/helpch/placeholderapi/expansion/server/ServerExpansion has been compiled by a more recent version of the Java Runtime (class file version 61.0), this version of the Java Runtime only recognizes class file versions up to 52.0
        at java.lang.ClassLoader.defineClass1(Native Method) ~[?:1.8.0_312]
        at java.lang.ClassLoader.defineClass(ClassLoader.java:756) ~[?:1.8.0_312]
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) ~[?:1.8.0_312]
        at java.net.URLClassLoader.defineClass(URLClassLoader.java:473) ~[?:1.8.0_312]
        at java.net.URLClassLoader.access$100(URLClassLoader.java:74) ~[?:1.8.0_312]
        at java.net.URLClassLoader$1.run(URLClassLoader.java:369) ~[?:1.8.0_312]
        at java.net.URLClassLoader$1.run(URLClassLoader.java:363) ~[?:1.8.0_312]
        at java.security.AccessController.doPrivileged(Native Method) ~[?:1.8.0_312]
        at java.net.URLClassLoader.findClass(URLClassLoader.java:362) ~[?:1.8.0_312]
        at java.lang.ClassLoader.loadClass(ClassLoader.java:418) ~[?:1.8.0_312]
        at java.lang.ClassLoader.loadClass(ClassLoader.java:351) ~[?:1.8.0_312]
        at me.clip.placeholderapi.util.FileUtil.findClass(FileUtil.java:62) ~[?:?]
        at me.clip.placeholderapi.expansion.manager.LocalExpansionManager.lambda$findExpansionInFile$7(LocalExpansionManager.java:421) ~[?:?]
        at java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1604) ~[?:1.8.0_312]
        ... 5 more