Pycharm 2019.1 Jupyter Notebook - Run Error

I'm running Pycharm 2019.1 and am very excited about the Jupyter Notebook support. I tested on my Windows installation, and it worked great - just like I wanted. 

But on my Linux installation (RHEL 6.9), when I execute a cell, which auto-starts a Notebook Server, I get a Run Error. The notebook server does start up in the background (I am able to log into it via a browser), but the embedded Notebook viewer in the right-pane never initializes, and I cannot execute cells in the editor pane. 

I already have a Jupyter configuration file set up, and the notebook server is starting from the directory specified in my config file. My current project is not in that directory. However, when I manually edited my config file to start the notebook from my project directory, I still get the same error. 

----- EDIT -----

Adding more info... 

These errors show up in idea.log as soon as I open a Notebook file. Do I need a particular Plugin to render the Notebook in the right-pane? 

2019-03-28 14:14:11,147 [  57698]  ERROR - llij.ide.plugins.PluginManager - ReferenceError: Can't find variable: ReactDOM
netscape.javascript.JSException: ReferenceError: Can't find variable: ReactDOM
        at com.sun.webkit.dom.JSObject.fwkMakeException(Unknown Source)
        at com.sun.webkit.WebPage.twkExecuteScript(Native Method)
        at com.sun.webkit.WebPage.executeScript(Unknown Source)
        at javafx.scene.web.WebEngine.executeScript(Unknown Source)
        at org.jetbrains.plugins.notebooks.jupyter.editor.preview.JupyterWebFrontendGateway.<init>(JupyterWebFrontendGateway.kt:56)
        at org.jetbrains.plugins.notebooks.jupyter.editor.preview.JupyterPreviewHtmlPanel.initPreview(JupyterPreviewHtmlPanel.kt:130)
        at org.jetbrains.plugins.notebooks.jupyter.editor.preview.JupyterPreviewHtmlPanel.access$initPreview(JupyterPreviewHtmlPanel.kt:49)
        at org.jetbrains.plugins.notebooks.jupyter.editor.preview.JupyterPreviewHtmlPanel$workerStateListener$1.changed(JupyterPreviewHtmlPanel.kt:68)
        at org.jetbrains.plugins.notebooks.jupyter.editor.preview.JupyterPreviewHtmlPanel$workerStateListener$1.changed(JupyterPreviewHtmlPanel.kt:59)
        at com.sun.javafx.binding.ExpressionHelper$Generic.fireValueChangedEvent(Unknown Source)
        at com.sun.javafx.binding.ExpressionHelper.fireValueChangedEvent(Unknown Source)
        at javafx.beans.property.ReadOnlyObjectWrapper$ReadOnlyPropertyImpl.fireValueChangedEvent(Unknown Source)
        at javafx.beans.property.ReadOnlyObjectWrapper.fireValueChangedEvent(Unknown Source)
        at javafx.beans.property.ObjectPropertyBase.markInvalid(Unknown Source)
        at javafx.beans.property.ObjectPropertyBase.set(Unknown Source)
        at javafx.scene.web.WebEngine$LoadWorker.updateState(Unknown Source)
        at javafx.scene.web.WebEngine$LoadWorker.dispatchLoadEvent(Unknown Source)
        at javafx.scene.web.WebEngine$LoadWorker.access$1100(Unknown Source)
        at javafx.scene.web.WebEngine$PageLoadListener.dispatchLoadEvent(Unknown Source)
        at com.sun.webkit.WebPage.fireLoadEvent(Unknown Source)
        at com.sun.webkit.WebPage.fwkFireLoadEvent(Unknown Source)
        at com.sun.webkit.network.URLLoader.twkDidFinishLoading(Native Method)
        at com.sun.webkit.network.URLLoader.notifyDidFinishLoading(Unknown Source)
        at com.sun.webkit.network.URLLoader.lambda$didFinishLoading$95(Unknown Source)
        at com.sun.webkit.network.URLLoader$$Lambda$3017/1036984217.run(Unknown Source)
        at com.sun.javafx.application.PlatformImpl.lambda$null$170(Unknown Source)
        at com.sun.javafx.application.PlatformImpl$$Lambda$2970/1963149081.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at com.sun.javafx.application.PlatformImpl.lambda$runLater$171(Unknown Source)
        at com.sun.javafx.application.PlatformImpl$$Lambda$2969/417009355.run(Unknown Source)
        at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(Unknown Source)
        at com.sun.glass.ui.gtk.GtkApplication._runLoop(Native Method)
        at com.sun.glass.ui.gtk.GtkApplication.lambda$null$48(Unknown Source)
        at com.sun.glass.ui.gtk.GtkApplication$$Lambda$2895/1265241239.run(Unknown Source)
        at java.lang.Thread.run(Unknown Source)
2019-03-28 14:14:11,149 [  57700]  ERROR - llij.ide.plugins.PluginManager - PyCharm 2019.1  Build #PY-191.6183.50
2019-03-28 14:14:11,149 [  57700]  ERROR - llij.ide.plugins.PluginManager - JDK: 1.8.0_45; VM: Java HotSpot(TM) 64-Bit Server VM; Vendor: Oracle Corporation
2019-03-28 14:14:11,149 [  57700]  ERROR - llij.ide.plugins.PluginManager - OS: Linux
2019-03-28 14:14:11,154 [  57705]  ERROR - llij.ide.plugins.PluginManager - Last Action:

When I attempt to execute a Notebook cell, this is what's in the log 

2019-03-28 14:17:23,797 [ 250348]   INFO - .intellij.util.EnvironmentUtil - loading shell env: /bin/bash -c . '/u/dramsoft/miniconda3/envs/cds/bin/activate' '/u/dramsoft/miniconda3/envs/cds';'/u/jlion/pycharm/pycharm-2019.1/bin/printenv.py' '/tmp/intellij-shell-env.tmp'
2019-03-28 14:17:25,910 [ 252461]   INFO - .intellij.util.EnvironmentUtil - shell environment loaded (352 vars)
2019-03-28 14:17:31,086 [ 257637]   WARN - r.actions.JupyterEditorActions - Jupyter error
org.jetbrains.plugins.notebooks.jupyter.connections.JupyterProcessException: [I 14:17:27.345 NotebookApp] The port 8888 is already in use, trying another port.
[I 14:17:27.356 NotebookApp] Serving notebooks from local directory: /u/jlion
[I 14:17:27.356 NotebookApp] The Jupyter Notebook is running at:
[I 14:17:27.356 NotebookApp] http://(jlion-lnx or 127.0.0.1):8889/jupyter/
[I 14:17:27.356 NotebookApp] Use Control-C to stop this server and shut down all kernels (twice to skip confirmation).

        at org.jetbrains.plugins.notebooks.jupyter.connections.JupyterNotebookProcessHandler.initJupyterServer(JupyterNotebookProcessHandler.kt:64)
        at org.jetbrains.plugins.notebooks.jupyter.connections.JupyterNotebookProcessHandler.access$initJupyterServer(JupyterNotebookProcessHandler.kt:30)
        at org.jetbrains.plugins.notebooks.jupyter.connections.JupyterNotebookProcessHandler$startNotify$1.run(JupyterNotebookProcessHandler.kt:107)
        at com.intellij.openapi.application.impl.ApplicationImpl$1.run(ApplicationImpl.java:311)
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
        at java.util.concurrent.FutureTask.run(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
        at java.lang.Thread.run(Unknown Source)