diff --git a/__mocks__/@electron/remote.js b/__mocks__/@electron/remote.js
index 0a7a1d42..ac02eb2b 100644
--- a/__mocks__/@electron/remote.js
+++ b/__mocks__/@electron/remote.js
@@ -1,5 +1,6 @@
 module.exports = {
   app: {
     getPath: () => '',
+    getLocale: () => '',
   },
 }
diff --git a/__mocks__/electron.js b/__mocks__/electron.js
index 34a8edb5..70fc8981 100644
--- a/__mocks__/electron.js
+++ b/__mocks__/electron.js
@@ -1,6 +1,7 @@
 module.exports = {
   app: {
     getPath: jest.fn(),
+    getLocale: jest.fn(),
   },
   ipcRenderer: {
     on: jest.fn(),
diff --git a/app/background/background.js b/app/background/background.js
index dd950457..22ac01de 100644
--- a/app/background/background.js
+++ b/app/background/background.js
@@ -15,9 +15,8 @@ on('initializePluginAsync', ({ name }) => {
   console.group(`Initialize async plugin ${name}`)
 
   try {
-    const { initializeAsync } = plugins[name]
-      ? plugins[name]
-      : window.require(`${modulesDirectory}/${name}`)
+    const plugin = plugins[name] || window.require(`${modulesDirectory}/${name}`)
+    const { initializeAsync } = plugin
 
     if (!initializeAsync) {
       console.log('no `initializeAsync` function, skipped')
@@ -29,11 +28,11 @@ on('initializePluginAsync', ({ name }) => {
       console.log('Done! Sending data back to main window')
       // Send message back to main window with initialization result
       send('plugin.message', { name, data })
-    }, pluginSettings.getUserSettings(name))
+    }, pluginSettings.getUserSettings(plugin, name))
   } catch (err) { console.log('Failed', err) }
 
   console.groupEnd()
 })
 
 // Handle `reload` rpc event and reload window
-on('reload', () => location.reload())
+on('reload', () => window.location.reload())
diff --git a/app/lib/__tests__/loadThemes.spec.js b/app/lib/__tests__/loadThemes.spec.js
new file mode 100644
index 00000000..b07d96cb
--- /dev/null
+++ b/app/lib/__tests__/loadThemes.spec.js
@@ -0,0 +1,32 @@
+import themesLoader from '../loadThemes'
+
+const productionThemes = [
+  {
+    value: '../dist/main/css/themes/light.css',
+    label: 'Light'
+  },
+  {
+    value: '../dist/main/css/themes/dark.css',
+    label: 'Dark'
+  }
+]
+
+const developmentThemes = [
+  {
+    value: 'http://localhost:3000/dist/main/css/themes/light.css',
+    label: 'Light'
+  },
+  {
+    value: 'http://localhost:3000/dist/main/css/themes/dark.css',
+    label: 'Dark'
+  }
+]
+
+test('returns themes for production', () => {
+  expect(themesLoader()).toEqual(productionThemes)
+})
+
+test('returns themes for development', () => {
+  process.env.NODE_ENV = 'development'
+  expect(themesLoader()).toEqual(developmentThemes)
+})
diff --git a/app/lib/config.js b/app/lib/config.js
index 254e9975..f23d4102 100644
--- a/app/lib/config.js
+++ b/app/lib/config.js
@@ -47,6 +47,16 @@ const readConfig = () => {
   try {
     return JSON.parse(fs.readFileSync(CONFIG_FILE).toString())
   } catch (err) {
+    const config = defaultSettings()
+
+    if (err.code !== 'ENOENT') {
+      console.error('Error reading config file', err)
+      return config
+    }
+
+    if (process.env.NODE_ENV === 'test') return config
+
+    fs.writeFileSync(CONFIG_FILE, JSON.stringify(config, null, 2))
     return defaultSettings()
   }
 }
@@ -57,14 +67,7 @@ const readConfig = () => {
  * @return {Any}
  */
 const get = (key) => {
-  let config
-
-  if (!fs.existsSync(CONFIG_FILE)) {
-    // Save default config to local storage
-    config = defaultSettings()
-    fs.writeFileSync(CONFIG_FILE, JSON.stringify(config, null, 2))
-  } else { config = readConfig() }
-
+  const config = readConfig()
   return config[key]
 }
 
diff --git a/app/lib/initPlugin.js b/app/lib/initPlugin.js
new file mode 100644
index 00000000..95e27291
--- /dev/null
+++ b/app/lib/initPlugin.js
@@ -0,0 +1,29 @@
+import { send } from 'lib/rpc'
+import { settings as pluginSettings } from 'lib/plugins'
+
+/**
+ * Initialices plugin sync and/or async by calling the `initialize` and `initializeAsync` functions
+ * @param {Object} plugin A plugin object
+ * @param {string} name The name entry in the plugin package.json
+ */
+const initPlugin = (plugin, name) => {
+  const { initialize, initializeAsync } = plugin
+
+  // Foreground plugin initialization
+  if (initialize) {
+    console.log('Initialize sync plugin', name)
+    try {
+      initialize(pluginSettings.getUserSettings(plugin, name))
+    } catch (e) {
+      console.error(`Failed to initialize plugin: ${name}`, e)
+    }
+  }
+
+  // Background plugin initialization
+  if (initializeAsync) {
+    console.log('Initialize async plugin', name)
+    send('initializePluginAsync', { name })
+  }
+}
+
+export default initPlugin
diff --git a/app/lib/initializePlugins.js b/app/lib/initializePlugins.js
index 8a733ccc..1112434b 100644
--- a/app/lib/initializePlugins.js
+++ b/app/lib/initializePlugins.js
@@ -1,27 +1,9 @@
-import { on, send } from 'lib/rpc'
+import { on } from 'lib/rpc'
 import plugins from 'plugins'
-import { settings as pluginSettings } from 'lib/plugins'
-
-export const initializePlugin = (name) => {
-  const { initialize, initializeAsync } = plugins[name]
-
-  if (initialize) {
-    // Foreground plugin initialization
-    try {
-      initialize(pluginSettings.getUserSettings(name))
-    } catch (e) {
-      console.error(`Failed to initialize plugin: ${name}`, e)
-    }
-  }
-
-  if (initializeAsync) {
-    // Background plugin initialization
-    send('initializePluginAsync', { name })
-  }
-}
+import initPlugin from './initPlugin'
 
 /**
- * RPC-call for plugins initializations
+ * Starts listening for `initializePlugin` events and initializes all plugins
  */
 export default () => {
   // Start listening for replies from plugin async initializers
@@ -30,5 +12,5 @@ export default () => {
     if (plugin.onMessage) plugin.onMessage(data)
   })
 
-  Object.keys(plugins).forEach(initializePlugin)
+  Object.keys(plugins).forEach((name) => initPlugin(plugins[name], name))
 }
diff --git a/app/lib/plugins/settings/__tests__/get.spec.js b/app/lib/plugins/settings/__tests__/get.spec.js
new file mode 100644
index 00000000..090f3ba7
--- /dev/null
+++ b/app/lib/plugins/settings/__tests__/get.spec.js
@@ -0,0 +1,21 @@
+import getUserSettings from '../get'
+
+const plugin = {
+  settings: {
+    test_setting1: {
+      type: 'string',
+      defaultValue: 'test',
+    },
+    test_setting2: {
+      type: 'number',
+      defaultValue: 1,
+    },
+  }
+}
+
+describe('Test getUserSettings', () => {
+  it('returns valid settings object', () => {
+    expect(getUserSettings(plugin, 'test-plugin'))
+      .toEqual({ test_setting1: 'test', test_setting2: 1 })
+  })
+})
diff --git a/app/lib/plugins/settings/__tests__/validate.spec.js b/app/lib/plugins/settings/__tests__/validate.spec.js
new file mode 100644
index 00000000..b2aa6fdd
--- /dev/null
+++ b/app/lib/plugins/settings/__tests__/validate.spec.js
@@ -0,0 +1,84 @@
+import validate from '../validate'
+
+const validSettings = {
+  option1: {
+    description: 'Just a test description',
+    type: 'option',
+    options: ['option_1', 'option_2'],
+  },
+  option2: {
+    description: 'Just a test description',
+    type: 'number',
+    defaultValue: 0
+  },
+  option3: {
+    description: 'Just a test description',
+    type: 'number',
+    defaultValue: 0
+  },
+  option4: {
+    description: 'Just a test description',
+    type: 'bool'
+  },
+  option5: {
+    description: 'Just a test description',
+    type: 'string',
+    defaultValue: 'test'
+  }
+}
+
+const invalidSettingsNoOptionsProvided = {
+  option1: {
+    description: 'Just a test description',
+    type: 'option',
+    options: [],
+  }
+}
+
+const invalidSettingsInvalidType = {
+  option1: {
+    description: 'Just a test description',
+    type: 'test'
+  }
+}
+
+describe('Validate settings function', () => {
+  it('returns true when plugin has no settings field', () => {
+    const plugin = {
+      fn: () => {}
+    }
+    expect(validate(plugin)).toEqual(true)
+  })
+
+  it('returns true when plugin has empty settings field', () => {
+    const plugin = {
+      fn: () => {},
+      settings: {}
+    }
+    expect(validate(plugin)).toEqual(true)
+  })
+
+  it('returns true when plugin has valid settings', () => {
+    const plugin = {
+      fn: () => {},
+      settings: validSettings
+    }
+    expect(validate(plugin)).toEqual(true)
+  })
+
+  it('returns false when option type is options and no options provided', () => {
+    const plugin = {
+      fn: () => {},
+      settings: invalidSettingsNoOptionsProvided
+    }
+    expect(validate(plugin)).toEqual(false)
+  })
+
+  it('returns false when option type is incorrect', () => {
+    const plugin = {
+      fn: () => {},
+      settings: invalidSettingsInvalidType
+    }
+    expect(validate(plugin)).toEqual(false)
+  })
+})
diff --git a/app/lib/plugins/settings/get.js b/app/lib/plugins/settings/get.js
index dc7685d4..6748c95f 100644
--- a/app/lib/plugins/settings/get.js
+++ b/app/lib/plugins/settings/get.js
@@ -1,19 +1,34 @@
 import config from 'lib/config'
-import plugins from 'plugins'
 
-const getSettings = pluginName => config.get('plugins')[pluginName] || {}
+/**
+ * Returns the settings established by the user and previously saved in the config file
+ * @param {string} pluginName The name entry of the plugin package.json
+ * @returns An object with keys and values of the **stored** plugin settings
+ */
+const getExistingSettings = (pluginName) => config.get('plugins')[pluginName] || {}
 
-const getUserSettings = (pluginName) => {
-  const settings = getSettings(pluginName)
+/**
+ * Returns the sum of the default settings and the user settings
+ * We use packageJsonName to avoid conflicts with plugins that export
+ * a different name from the bundle. Two plugins can export the same name
+ * but can't have the same package.json name
+ * @param {Object} plugin
+ * @param {string} packageJsonName
+ * @returns An object with keys and values of the plugin settings
+ */
+const getUserSettings = (plugin, packageJsonName) => {
+  const userSettings = {}
+  const existingSettings = getExistingSettings(packageJsonName)
+  const { settings: pluginSettings } = plugin
 
-  if (plugins[pluginName].settings) {
+  if (pluginSettings) {
     // Provide default values if nothing is set by user
-    Object.keys(plugins[pluginName].settings).forEach((key) => {
-      settings[key] = settings[key] || plugins[pluginName].settings[key].defaultValue
+    Object.keys(pluginSettings).forEach((key) => {
+      userSettings[key] = existingSettings[key] || pluginSettings[key].defaultValue
     })
   }
 
-  return settings
+  return userSettings
 }
 
 export default getUserSettings
diff --git a/app/main/actions/search.spec.js b/app/main/actions/__tests__/search.spec.js
similarity index 97%
rename from app/main/actions/search.spec.js
rename to app/main/actions/__tests__/search.spec.js
index c3743cc6..8e5d1fc3 100644
--- a/app/main/actions/search.spec.js
+++ b/app/main/actions/__tests__/search.spec.js
@@ -10,7 +10,7 @@ import {
   RESET,
 } from 'main/constants/actionTypes'
 
-import * as actions from './search'
+import * as actions from '../search'
 
 describe('reset', () => {
   it('returns valid action', () => {
diff --git a/app/main/actions/__tests__/statusBar.spec.js b/app/main/actions/__tests__/statusBar.spec.js
new file mode 100644
index 00000000..bd6f70ee
--- /dev/null
+++ b/app/main/actions/__tests__/statusBar.spec.js
@@ -0,0 +1,27 @@
+/**
+ * @jest-environment jsdom
+ */
+
+import {
+  SET_STATUS_BAR_TEXT
+} from 'main/constants/actionTypes'
+
+import * as actions from '../statusBar'
+
+describe('reset', () => {
+  it('returns valid action', () => {
+    expect(actions.reset()).toEqual({
+      type: SET_STATUS_BAR_TEXT,
+      payload: null
+    })
+  })
+})
+
+describe('setValue', () => {
+  it('returns valid action when value passed', () => {
+    expect(actions.setValue('test value')).toEqual({
+      type: SET_STATUS_BAR_TEXT,
+      payload: 'test value'
+    })
+  })
+})
diff --git a/app/main/actions/search.js b/app/main/actions/search.js
index 4fb70476..f8e23657 100644
--- a/app/main/actions/search.js
+++ b/app/main/actions/search.js
@@ -28,10 +28,10 @@ const remote = process.type === 'browser'
 const DEFAULT_SCOPE = {
   config,
   actions: {
-    open: q => shell.openExternal(q),
-    reveal: q => shell.showItemInFolder(q),
-    copyToClipboard: q => clipboard.writeText(q),
-    replaceTerm: term => store.dispatch(updateTerm(term)),
+    open: (q) => shell.openExternal(q),
+    reveal: (q) => shell.showItemInFolder(q),
+    copyToClipboard: (q) => clipboard.writeText(q),
+    replaceTerm: (term) => store.dispatch(updateTerm(term)),
     hideWindow: () => remote.getCurrentWindow().hide()
   }
 }
@@ -39,19 +39,20 @@ const DEFAULT_SCOPE = {
 /**
  * Pass search term to all plugins and handle their results
  * @param {String} term Search term
- * @param {Function} callback Callback function that receives used search term and found results
+ * @param {Function} display Callback function that receives used search term and found results
  */
 const eachPlugin = (term, display) => {
   // TODO: order results by frequency?
   Object.keys(plugins).forEach((name) => {
+    const plugin = plugins[name]
     try {
-      plugins[name].fn({
+      plugin.fn({
         ...DEFAULT_SCOPE,
         term,
-        hide: id => store.dispatch(hideElement(`${name}-${id}`)),
+        hide: (id) => store.dispatch(hideElement(`${name}-${id}`)),
         update: (id, result) => store.dispatch(updateElement(`${name}-${id}`, result)),
-        display: payload => display(name, payload),
-        settings: pluginSettings.getUserSettings(name)
+        display: (payload) => display(name, payload),
+        settings: pluginSettings.getUserSettings(plugin, name)
       })
     } catch (error) {
       // Do not fail on plugin errors, just log them to console
@@ -60,12 +61,11 @@ const eachPlugin = (term, display) => {
   })
 }
 
-
 /**
  * Handle results found by plugin
  *
  * @param  {String} term Search term that was used for found results
- * @param  {Array or Object} result Found results (or result)
+ * @param  {Array | Object} result Found results (or result)
  * @return {Object}  redux action
  */
 function onResultFound(term, result) {
@@ -78,7 +78,6 @@ function onResultFound(term, result) {
   }
 }
 
-
 /**
  * Action that clears everthing in search box
  *
@@ -104,7 +103,7 @@ export function updateTerm(term) {
     })
     eachPlugin(term, (plugin, payload) => {
       let result = Array.isArray(payload) ? payload : [payload]
-      result = result.map(x => ({
+      result = result.map((x) => ({
         ...x,
         plugin,
         // Scope result ids with plugin name and use title if id is empty
@@ -121,8 +120,8 @@ export function updateTerm(term) {
 
 /**
  * Action to move highlighted cursor to next or prev element
- * @param  {Integer} diff 1 or -1
- * @return {Object}  redux action
+ * @param  {1 | -1} diff
+ * @return {Object} redux action
  */
 export function moveCursor(diff) {
   return {
@@ -133,8 +132,8 @@ export function moveCursor(diff) {
 
 /**
  * Action to change highlighted element
- * @param  {Integer} index of new highlighted element
- * @return {Object}  redux action
+ * @param  {number} index Index of new highlighted element
+ * @return {Object} redux action
  */
 export function selectElement(index) {
   return {
@@ -146,7 +145,7 @@ export function selectElement(index) {
 /**
  * Action to remove element from results list by id
  * @param  {String} id
- * @return {Object}  redux action
+ * @return {Object} redux action
  */
 export function hideElement(id) {
   return {
diff --git a/app/plugins/core/index.js b/app/plugins/core/index.js
index 27139254..78ec4a21 100644
--- a/app/plugins/core/index.js
+++ b/app/plugins/core/index.js
@@ -5,4 +5,6 @@ import settings from './settings'
 import version from './version'
 import reload from './reload'
 
-export default { autocomplete, quit, plugins, settings, version, reload }
+export default {
+  autocomplete, quit, plugins, settings, version, reload
+}
diff --git a/app/plugins/externalPlugins.js b/app/plugins/externalPlugins.js
index a3a13790..ecbcf5fe 100644
--- a/app/plugins/externalPlugins.js
+++ b/app/plugins/externalPlugins.js
@@ -1,7 +1,7 @@
 import debounce from 'lodash/debounce'
 import chokidar from 'chokidar'
 import path from 'path'
-import { initializePlugin } from 'lib/initializePlugins'
+import initPlugin from 'lib/initPlugin'
 import { modulesDirectory, ensureFiles, settings } from 'lib/plugins'
 
 const requirePlugin = (pluginPath) => {
@@ -99,8 +99,7 @@ pluginsWatcher.on('addDir', (pluginPath) => {
     }, 1000))
     plugins[pluginName] = plugin
     if (!global.isBackground) {
-      console.log('Initialize async plugin', pluginName)
-      initializePlugin(pluginName)
+      initPlugin(plugin, pluginName)
     }
     console.groupEnd()
   }, 1000)
diff --git a/jest.config.js b/jest.config.js
index ae5b00b5..c70394f1 100644
--- a/jest.config.js
+++ b/jest.config.js
@@ -1,4 +1,5 @@
 module.exports = {
+  collectCoverage: true,
   moduleDirectories: ['node_modules', 'app'],
   moduleNameMapper: {
     '\\.(jpg|ico|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$': '<rootDir>/__mocks__/fileMock.js',