NullPointerException when trying to rename PHP variable

[ofry]

IntelliJ IDEA 2018.3 (Ultimate Edition)
Build #IU-183.4284.148, built on November 21, 2018

JRE: 1.8.0_152-release-1343-b15 amd64
JVM: OpenJDK 64-Bit Server VM by JetBrains s.r.o
Kubuntu 18.10 x64

Markup to SCSS v0.2.1

update failed for AnAction(com.xcodersteam.idea.plugins.mkupscss.GenerateSCSSAction) with ID=MarkupToSCSS

java.lang.NullPointerException
	at com.xcodersteam.idea.plugins.mkupscss.GenerateSCSSAction.update(GenerateSCSSAction.scala:27)
	at com.intellij.openapi.actionSystem.ex.ActionUtil.performDumbAwareUpdate(ActionUtil.java:171)
	at com.intellij.openapi.actionSystem.impl.Utils.doUpdate(Utils.java:202)
	at com.intellij.openapi.actionSystem.impl.Utils.expandActionGroup(Utils.java:151)
	at com.intellij.openapi.actionSystem.impl.Utils.fillMenu(Utils.java:295)
	at com.intellij.openapi.actionSystem.impl.ActionPopupMenuImpl$MyMenu.show(ActionPopupMenuImpl.java:109)
	at com.intellij.openapi.editor.impl.EditorImpl.invokePopupIfNeeded(EditorImpl.java:4633)
	at com.intellij.openapi.editor.impl.EditorImpl.access$9400(EditorImpl.java:124)
	at com.intellij.openapi.editor.impl.EditorImpl$MyMouseAdapter.runMousePressedCommand(EditorImpl.java:3700)
	at com.intellij.openapi.editor.impl.EditorImpl$MyMouseAdapter.mousePressed(EditorImpl.java:3624)
	at java.awt.Component.processMouseEvent(Component.java:6545)
	at javax.swing.JComponent.processMouseEvent(JComponent.java:3325)
	at java.awt.Component.processEvent(Component.java:6313)
	at java.awt.Container.processEvent(Container.java:2237)
	at java.awt.Component.dispatchEventImpl(Component.java:4903)
	at java.awt.Container.dispatchEventImpl(Container.java:2295)
	at java.awt.Component.dispatchEvent(Component.java:4725)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4889)
	at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4523)
	at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4467)
	at java.awt.Container.dispatchEventImpl(Container.java:2281)
	at java.awt.Window.dispatchEventImpl(Window.java:2746)
	at java.awt.Component.dispatchEvent(Component.java:4725)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:764)
	at java.awt.EventQueue.access$500(EventQueue.java:98)
	at java.awt.EventQueue$3.run(EventQueue.java:715)
	at java.awt.EventQueue$3.run(EventQueue.java:709)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:90)
	at java.awt.EventQueue$4.run(EventQueue.java:737)
	at java.awt.EventQueue$4.run(EventQueue.java:735)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:734)
	at com.intellij.ide.IdeEventQueue.defaultDispatchEvent(IdeEventQueue.java:719)
	at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.java:664)
	at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.java:363)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)