message: Fix style of the preferences dialog (linux)
diff: <string>Preferences</string>
  </property>
  <property name="styleSheet">
  - <string notr="true">color:rgb(85, 85, 85);font-size:13px;</string>
  + <string notr="true">font-size:13px;</string>
  </property>
  <layout class="QVBoxLayout" name="verticalLayout_3">
  <item>
  <layout class="QGridLayout" name="gridLayout_3" columnstretch="1,0,0">
  <item row="0" column="0">
  <widget class="QCheckBox" name="pomodoroTimer">
  - <property name="styleSheet">
  - <string notr="true">color:rgb(85, 85, 85);</string>
  - </property>
  <property name="text">
  <string>Pomodoro timer</string>
  </property>
  </item>
  <item row="1" column="0">
  <widget class="QCheckBox" name="pomodoroBreakTimer">
  - <property name="styleSheet">
  - <string notr="true">color:rgb(85, 85, 85);</string>
  - </property>
  <property name="text">
  <string>Pomodoro break timer</string>
  </property>
  </item>
  <item row="2" column="0">
  <widget class="QCheckBox" name="idleDetection">
  - <property name="styleSheet">
  - <string notr="true">color:rgb(85, 85, 85);</string>
  - </property>
  <property name="text">
  <string>Idle detection</string>
  </property>
  </item>
  <item row="3" column="0">
  <widget class="QCheckBox" name="recordTimeline">
  - <property name="styleSheet">
  - <string notr="true">color:rgb(85, 85, 85);</string>
  - </property>
  <property name="text">
  <string>Record timeline</string>
  </property>
  <property name="toolTip">
  <string>Clear shortcut</string>
  </property>
  - <property name="styleSheet">
  - <string notr="true"/>
  - </property>
  <property name="text">
  <string>x</string>
  </property>
  <property name="toolTip">
  <string>Clear Shortcut</string>
  </property>
  - <property name="styleSheet">
  - <string notr="true"/>
  - </property>
  <property name="text">
  <string>x</string>
  </property>
  </item>
  <item row="2" column="0">
  <widget class="QCheckBox" name="focusAppOnShortcut">
  - <property name="styleSheet">
  - <string notr="true">color:rgb(85, 85, 85);</string>
  - </property>
  <property name="text">
  <string>Focus app on shortcut</string>
  </property>
  <layout class="QVBoxLayout" name="verticalLayout_2">
  <item>
  <widget class="QCheckBox" name="useSystemProxySettings">
  - <property name="styleSheet">
  - <string notr="true">color:rgb(85, 85, 85);</string>
  - </property>
  <property name="text">
  <string>Use system proxy settings</string>
  </property>
  </item>
  <item row="1" column="0">
  <widget class="QCheckBox" name="remindToTrackTime">
  - <property name="styleSheet">
  - <string notr="true">color:rgb(85, 85, 85);</string>
  - </property>
  <property name="text">
  <string>Remind to track time</string>
  </property>
  