remove highlights on unload

apps/remix-ide/src/app/tabs/debugger-tab.js

@@ -61,7 +61,8 @@ class DebuggerTab extends ViewPlugin {
       (address, receipt) => {
         const target = (address && remixLib.helpers.trace.isContractCreation(address)) ? receipt.contractAddress : address
         return this.call('fetchAndCompile', 'resolve', target || receipt.contractAddress || receipt.to, '.debug', this.blockchain.web3())
-      })
+      }
+    )
 
     this.call('manager', 'activatePlugin', 'source-verification')
     // this.call('manager', 'activatePlugin', 'udapp')
@@ -69,6 +70,11 @@ class DebuggerTab extends ViewPlugin {
     return this.el
   }
 
+  deactivate () {
+    this.debuggerUI.unLoad()
+    super.deactivate()
+  }
+
   debug (hash) {
     if (this.debuggerUI) this.debuggerUI.debug(hash)
   }

apps/remix-ide/src/app/tabs/debugger/debuggerUI.js

@@ -206,7 +206,8 @@ class DebuggerUI {
     return view
   }
 
-  unLoad () {
+  async unLoad () {
+    await this.debuggerModule.call('editor', 'discardHighlight')
     yo.update(this.debuggerHeadPanelsView, yo`<div></div>`)
     yo.update(this.debuggerPanelsView, yo`<div></div>`)
     yo.update(this.stepManagerView, yo`<div></div>`)