4 files changed, 10 insertions, 28 deletions
diff --git a/devtools/client/framework/devtools.js b/devtools/client/framework/devtools.js
index 90f88023b..976a4b56d 100644
--- a/devtools/client/framework/devtools.js
+++ b/devtools/client/framework/devtools.js
@@ -195,12 +195,7 @@ DevTools.prototype = {
       return tool;
     }
 
-    let enabled;
-    try {
-      enabled = Services.prefs.getBoolPref(tool.visibilityswitch);
-    } catch (e) {
-      enabled = true;
-    }
+    let enabled = Services.prefs.getBoolPref(tool.visibilityswitch, true);
 
     return enabled ? tool : null;
   },
diff --git a/devtools/client/framework/toolbox-process-window.js b/devtools/client/framework/toolbox-process-window.js
index 8ead718b3..8f75e3e24 100644
--- a/devtools/client/framework/toolbox-process-window.js
+++ b/devtools/client/framework/toolbox-process-window.js
@@ -100,17 +100,12 @@ function openToolbox({ form, chrome, isTabActor }) {
   };
   TargetFactory.forRemoteTab(options).then(target => {
     let frame = document.getElementById("toolbox-iframe");
-    let selectedTool = "jsdebugger";
-
-    try {
-      // Remember the last panel that was used inside of this profile.
-      selectedTool = Services.prefs.getCharPref("devtools.toolbox.selectedTool");
-    } catch(e) {}
-
-    try {
-      // But if we are testing, then it should always open the debugger panel.
-      selectedTool = Services.prefs.getCharPref("devtools.browsertoolbox.panel");
-    } catch(e) {}
+    // Remember the last panel that was used inside of this profile.
+    // But if we are testing, then it should always open the debugger panel.
+    let selectedTool =
+      Services.prefs.getCharPref("devtools.browsertoolbox.panel",
+                                 Services.prefs.getCharPref("devtools.toolbox.selectedTool",
+                                                            "jsdebugger"));
 
     let options = { customIframe: frame };
     gDevTools.showToolbox(target,
diff --git a/devtools/client/framework/toolbox.js b/devtools/client/framework/toolbox.js
index 926e30647..cde7de0e4 100644
--- a/devtools/client/framework/toolbox.js
+++ b/devtools/client/framework/toolbox.js
@@ -1131,12 +1131,7 @@ Toolbox.prototype = {
   setToolboxButtonsVisibility: function () {
     this.toolboxButtons.forEach(buttonSpec => {
       let { visibilityswitch, button, isTargetSupported } = buttonSpec;
-      let on = true;
-      try {
-        on = Services.prefs.getBoolPref(visibilityswitch);
-      } catch (ex) {
-        // Do nothing.
-      }
+      let on = Services.prefs.getBoolPref(visibilityswitch, true);
 
       on = on && isTargetSupported(this.target);
 
diff --git a/devtools/client/inspector/markup/markup.js b/devtools/client/inspector/markup/markup.js
index d6e9f8c11..a4b65c899 100644
--- a/devtools/client/inspector/markup/markup.js
+++ b/devtools/client/inspector/markup/markup.js
@@ -73,11 +73,8 @@ function MarkupView(inspector, frame, controllerWindow) {
   this._elt = this.doc.querySelector("#root");
   this.htmlEditor = new HTMLEditor(this.doc);
 
-  try {
-    this.maxChildren = Services.prefs.getIntPref("devtools.markup.pagesize");
-  } catch (ex) {
-    this.maxChildren = DEFAULT_MAX_CHILDREN;
-  }
+  this.maxChildren = Services.prefs.getIntPref("devtools.markup.pagesize",
+                                               DEFAULT_MAX_CHILDREN);
 
   this.collapseAttributes =
     Services.prefs.getBoolPref(ATTR_COLLAPSE_ENABLED_PREF);