diff --git a/gui/chrome_tabs.py b/gui/chrome_tabs.py
index b50073565..66c1c262e 100644
--- a/gui/chrome_tabs.py
+++ b/gui/chrome_tabs.py
@@ -736,6 +736,7 @@ class _TabsContainer(wx.Panel):
         self.Bind(wx.EVT_ERASE_BACKGROUND, self.OnErase)
         self.Bind(wx.EVT_LEFT_DOWN, self.OnLeftDown)
         self.Bind(wx.EVT_LEFT_UP, self.OnLeftUp)
+        self.Bind(wx.EVT_MIDDLE_UP, self.OnMiddleUp)
         self.Bind(wx.EVT_MOTION, self.OnMotion)
         self.Bind(wx.EVT_SIZE, self.OnSize)
         self.Bind(wx.EVT_SYS_COLOUR_CHANGED, self.OnSysColourChanged)
@@ -776,6 +777,29 @@ class _TabsContainer(wx.Panel):
 
             self.dragged_tab = tab
 
+    def OnMiddleUp(self, event):
+        mposx, mposy = event.GetPosition()
+
+        tab = self.FindTabAtPos(mposx, mposy)
+
+        if tab is None or not tab.closeable:  # if not able to close, return False
+            return False
+
+        index = self.tabs.index(tab)
+        ev = PageClosing(index)
+        wx.PostEvent(self.Parent, ev)
+
+        if ev.isVetoed():
+            return False
+
+        index = self.GetTabIndex(tab)
+        self.Parent.DeletePage(index)
+        wx.PostEvent(self.Parent, PageClosed(index=index))
+
+        sel = self.GetSelected()
+        if sel is not None:
+            wx.PostEvent(self.Parent, PageChanged(-1, sel))
+
     def OnMotion(self, event):
         """
         Determines what happens when the mouse moves. This handles primarily
diff --git a/gui/fitCommands/calc/fitReplaceModule.py b/gui/fitCommands/calc/fitReplaceModule.py
index 19674df80..b7edf21b4 100644
--- a/gui/fitCommands/calc/fitReplaceModule.py
+++ b/gui/fitCommands/calc/fitReplaceModule.py
@@ -23,6 +23,13 @@ class FitReplaceModuleCommand(wx.Command):
         self.old_module = None
 
     def Do(self):
+        fit = eos.db.getFit(self.fitID)
+
+        mod = fit.modules[self.position]
+        if not mod.isEmpty:
+            self.old_module = ModuleInfoCache(mod.modPosition, mod.item.ID, mod.state, mod.charge, mod.baseItemID,
+                                              mod.mutaplasmidID)
+
         return self.change_module(self.fitID, self.position, self.itemID)
 
     def Undo(self):
@@ -30,7 +37,6 @@ class FitReplaceModuleCommand(wx.Command):
             fit = eos.db.getFit(self.fitID)
             fit.modules.toDummy(self.position)
             return True
-
         self.change_module(self.fitID, self.position, self.old_module.itemID)
         self.module.state = self.old_module.state
         self.module.charge = self.old_module.charge
@@ -52,10 +58,7 @@ class FitReplaceModuleCommand(wx.Command):
         pyfalog.debug("Changing position of module from position ({0}) for fit ID: {1}", self.position, fitID)
 
         item = eos.db.getItem(itemID, eager=("attributes", "group.category"))
-
         mod = fit.modules[self.position]
-        if not mod.isEmpty:
-            self.old_module = ModuleInfoCache(mod.modPosition, mod.item.ID, mod.state, mod.charge, mod.baseItemID, mod.mutaplasmidID)
 
         try:
             self.module = Module(item)
@@ -75,6 +78,9 @@ class FitReplaceModuleCommand(wx.Command):
             if self.module.isValidState(State.ACTIVE):
                 self.module.state = State.ACTIVE
 
+            if self.old_module.charge and self.module.isValidCharge(self.old_module.charge):
+                self.module.charge = self.old_module.charge
+
             # Then, check states of all modules and change where needed. This will recalc if needed
             # self.checkStates(fit, m)