diff --git a/frontend/apps/reader/modules/readercropping.lua b/frontend/apps/reader/modules/readercropping.lua
index 55404dc9f..a24174be5 100644
--- a/frontend/apps/reader/modules/readercropping.lua
+++ b/frontend/apps/reader/modules/readercropping.lua
@@ -148,7 +148,6 @@ function ReaderCropping:exitPageCrop(confirmed)
     else
         self:setCropZoomMode(confirmed)
     end
-    UIManager.repaint_all = true
 end
 
 function ReaderCropping:setCropZoomMode(confirmed)
diff --git a/frontend/apps/reader/modules/readerfooter.lua b/frontend/apps/reader/modules/readerfooter.lua
index 574baf19d..05b87ccb0 100644
--- a/frontend/apps/reader/modules/readerfooter.lua
+++ b/frontend/apps/reader/modules/readerfooter.lua
@@ -267,22 +267,19 @@ function ReaderFooter:onTapFooter(arg, ges)
             self.mode = 0
         end
         self:applyFooterMode()
-        local region = Geom:new{
-            x = 0,
-            y = Screen:getHeight() - self.height,
-            w = Screen:getWidth(),
-            h = self.height
-        }
-        UIManager.update_regions_func = function()
-            return {region}
-        end
     end
     if self.pageno then
         self:updateFooterPage()
     else
         self:updateFooterPos()
     end
-    UIManager:setDirty(self.view.dialog, "partial")
+    local region = Geom:new{
+        x = 0,
+        y = Screen:getHeight() - self.height,
+        w = Screen:getWidth(),
+        h = self.height
+    }
+    UIManager:setDirty(self.view.dialog, "partial", region)
     G_reader_settings:saveSetting("reader_footer_mode", self.mode)
     return true
 end
diff --git a/frontend/apps/reader/modules/readerhighlight.lua b/frontend/apps/reader/modules/readerhighlight.lua
index 21d0f71e8..b642808c5 100644
--- a/frontend/apps/reader/modules/readerhighlight.lua
+++ b/frontend/apps/reader/modules/readerhighlight.lua
@@ -120,7 +120,6 @@ function ReaderHighlight:clear()
     else
         self.ui.document:clearSelection()
     end
-    UIManager:setDirty(self.dialog, "full")
     if self.hold_pos then
         self.hold_pos = nil
         self.selected_text = nil
@@ -240,13 +239,9 @@ function ReaderHighlight:onHold(arg, ges)
             table.insert(boxes, self.selected_word.sbox)
             self.view.highlight.temp[self.hold_pos.page] = boxes
         end
-        --[[
-        UIManager.update_regions_func = function()
-            DEBUG("update ReaderHighlight onHold region", self.selected_word.sbox)
-            return {self.selected_word.sbox}
-        end
-        --]]
         UIManager:setDirty(self.dialog, "partial")
+        -- TODO: only mark word?
+        -- UIManager:setDirty(self.dialog, "partial", self.selected_word.sbox)
     end
     return true
 end
@@ -265,7 +260,12 @@ function ReaderHighlight:onHoldPan(arg, ges)
 
     self.holdpan_pos = self.view:screenToPageTransform(ges.pos)
     DEBUG("holdpan position in page", self.holdpan_pos)
+    local old_text = self.selected_text and self.selected_text.text
     self.selected_text = self.ui.document:getTextFromPositions(self.hold_pos, self.holdpan_pos)
+    if self.selected_text and old_text and old_text == self.selected_text.text then
+        -- no modification
+        return
+    end
     DEBUG("selected text:", self.selected_text)
     if self.selected_text then
         self.view.highlight.temp[self.hold_pos.page] = self.selected_text.sboxes
diff --git a/frontend/apps/reader/modules/readerpaging.lua b/frontend/apps/reader/modules/readerpaging.lua
index 6b43d8662..e9381f7ed 100644
--- a/frontend/apps/reader/modules/readerpaging.lua
+++ b/frontend/apps/reader/modules/readerpaging.lua
@@ -314,7 +314,8 @@ function ReaderPaging:onSwipe(arg, ges)
             self:onPagingRel(-1)
         end
     else
-        UIManager.full_refresh = true
+        -- trigger full refresh
+        UIManager:setDirty(nil, "full")
     end
 end
 
@@ -343,7 +344,8 @@ function ReaderPaging:onPanRelease(arg, ges)
         end
     else
         self.last_pan_relative_y = 0
-        UIManager.full_refresh = true
+        -- trigger full refresh
+        UIManager:setDirty(nil, "full")
     end
 end
 
@@ -649,7 +651,7 @@ function ReaderPaging:onScrollPageRel(diff)
     end
     -- update current pageno to the very last part in current view
     self:gotoPage(self.view.page_states[#self.view.page_states].page, "scrolling")
-    UIManager:setDirty(self.view.dialog)
+    UIManager:setDirty(self.view.dialog, "partial")
 end
 
 function ReaderPaging:onGotoPageRel(diff)
diff --git a/frontend/apps/reader/modules/readerrolling.lua b/frontend/apps/reader/modules/readerrolling.lua
index 25ad6b4a8..83b4effad 100644
--- a/frontend/apps/reader/modules/readerrolling.lua
+++ b/frontend/apps/reader/modules/readerrolling.lua
@@ -389,7 +389,7 @@ function ReaderRolling:updatePos()
         self.old_page = new_page
         self.ui:handleEvent(Event:new("UpdateToc"))
     end
-    UIManager.repaint_all = true
+    UIManager:setDirty(self.view.dialog, "partial")
 end
 
 --[[
diff --git a/frontend/apps/reader/modules/readerscreenshot.lua b/frontend/apps/reader/modules/readerscreenshot.lua
index b500f4446..346adf2b6 100644
--- a/frontend/apps/reader/modules/readerscreenshot.lua
+++ b/frontend/apps/reader/modules/readerscreenshot.lua
@@ -42,7 +42,8 @@ function ReaderScreenshot:onScreenshot(filename)
         timeout = 2,
     })
     Screen:shot(screenshot_name)
-    UIManager.full_refresh = true
+    -- trigger full refresh
+    UIManager:setDirty(nil, "full")
     return true
 end
 
diff --git a/frontend/apps/reader/modules/readersearch.lua b/frontend/apps/reader/modules/readersearch.lua
index 8851d0156..a21aba836 100644
--- a/frontend/apps/reader/modules/readersearch.lua
+++ b/frontend/apps/reader/modules/readersearch.lua
@@ -71,6 +71,7 @@ function ReaderSearch:onShowSearchDialog(text)
     }
     local res = do_search(self.searchFromCurrent, text, 0)()
     UIManager:show(self.search_dialog)
+    -- TODO: regional
     UIManager:setDirty(self.dialog, "partial")
     return true
 end
diff --git a/frontend/apps/reader/modules/readerview.lua b/frontend/apps/reader/modules/readerview.lua
index e9f7c0273..d765fc27b 100644
--- a/frontend/apps/reader/modules/readerview.lua
+++ b/frontend/apps/reader/modules/readerview.lua
@@ -508,7 +508,7 @@ function ReaderView:recalculate()
         self.state.offset.x = (self.dimen.w - self.visible_area.w) / 2
     end
     -- flag a repaint so self:paintTo will be called
-    UIManager:setDirty(self.dialog)
+    UIManager:setDirty(self.dialog, "partial")
 end
 
 function ReaderView:PanningUpdate(dx, dy)
@@ -517,7 +517,7 @@ function ReaderView:PanningUpdate(dx, dy)
     self.visible_area:offsetWithin(self.page_area, dx, dy)
     if self.visible_area ~= old then
         -- flag a repaint
-        UIManager:setDirty(self.dialog)
+        UIManager:setDirty(self.dialog, "partial")
         DEBUG("on pan: page_area", self.page_area)
         DEBUG("on pan: visible_area", self.visible_area)
         self.ui:handleEvent(
@@ -534,7 +534,7 @@ function ReaderView:PanningStart(x, y)
     self.visible_area = self.panning_visible_area:copy()
     self.visible_area:offsetWithin(self.page_area, x, y)
     self.ui:handleEvent(Event:new("ViewRecalculate", self.visible_area, self.page_area))
-    UIManager:setDirty(self.dialog)
+    UIManager:setDirty(self.dialog, "partial")
 end
 
 function ReaderView:PanningStop()
@@ -546,7 +546,7 @@ function ReaderView:SetZoomCenter(x, y)
     self.visible_area:centerWithin(self.page_area, x, y)
     if self.visible_area ~= old then
         self.ui:handleEvent(Event:new("ViewRecalculate", self.visible_area, self.page_area))
-        UIManager:setDirty(self.dialog)
+        UIManager:setDirty(self.dialog, "partial")
     end
 end
 
diff --git a/frontend/ui/widget/bboxwidget.lua b/frontend/ui/widget/bboxwidget.lua
index ff108f47d..8c1a98ef2 100644
--- a/frontend/ui/widget/bboxwidget.lua
+++ b/frontend/ui/widget/bboxwidget.lua
@@ -190,7 +190,7 @@ function BBoxWidget:adjustScreenBBox(ges, relative)
         y1 = Math.round(bottom_right.y)
     }
 
-    UIManager.repaint_all = true
+    UIManager:setDirty("all")
 end
 
 function BBoxWidget:getModifiedPageBBox()
diff --git a/frontend/ui/widget/button.lua b/frontend/ui/widget/button.lua
index 6a2c0169b..bc35839bf 100644
--- a/frontend/ui/widget/button.lua
+++ b/frontend/ui/widget/button.lua
@@ -154,16 +154,16 @@ function Button:onTapSelectButton()
     if self.enabled and self.callback then
         UIManager:scheduleIn(0.0, function()
             self[1].invert = true
-            UIManager.update_regions_func = function()
-                return {self[1].dimen}
-            end
-            UIManager.repaint_all = true -- FIXME: Why?
-            UIManager:setDirty(self.show_parent, "partial")
+            UIManager:setDirty(self.show_parent, function()
+                return "partial", self[1].dimen
+            end)
         end)
         UIManager:scheduleIn(0.1, function()
             self.callback()
             self[1].invert = false
-            UIManager:setDirty(self.show_parent, "partial")
+            UIManager:setDirty(self.show_parent, function()
+                return "partial", self[1].dimen
+            end)
         end)
     end
     return true
diff --git a/frontend/ui/widget/configdialog.lua b/frontend/ui/widget/configdialog.lua
index c34e17d40..fc9d10b2a 100644
--- a/frontend/ui/widget/configdialog.lua
+++ b/frontend/ui/widget/configdialog.lua
@@ -70,10 +70,9 @@ function OptionTextItem:onTapSelect()
     self.config:onConfigChoose(self.values, self.name,
                     self.event, self.args,
                     self.events, self.current_item)
-    UIManager.update_regions_func = function()
-        return {self[1].dimen}
-    end
-    UIManager:setDirty(self.config, "partial")
+    UIManager:setDirty(self.config, function()
+        return "partial", self[1].dimen
+    end)
     return true
 end
 
@@ -125,10 +124,9 @@ function OptionIconItem:onTapSelect()
     self.config:onConfigChoose(self.values, self.name,
                     self.event, self.args,
                     self.events, self.current_item)
-    UIManager.update_regions_func = function()
-        return {self[1].dimen}
-    end
-    UIManager:setDirty(self.config, "partial")
+    UIManager:setDirty(self.config, function()
+        return "partial", self[1].dimen
+    end)
     return true
 end
 
@@ -525,7 +523,7 @@ end
 function ConfigDialog:onShowConfigPanel(index)
     self.panel_index = index
     self:update()
-    UIManager.repaint_all = true
+    UIManager:setDirty("all")
     return true
 end
 
@@ -563,7 +561,7 @@ function ConfigDialog:onConfigChoose(values, name, event, args, events, position
         if events then
             self:onConfigEvents(events, position)
         end
-        UIManager.repaint_all = true
+        UIManager:setDirty("all")
     end)
 end
 
diff --git a/frontend/ui/widget/dictquicklookup.lua b/frontend/ui/widget/dictquicklookup.lua
index 000f4d292..5c11dd4ad 100644
--- a/frontend/ui/widget/dictquicklookup.lua
+++ b/frontend/ui/widget/dictquicklookup.lua
@@ -256,8 +256,7 @@ function DictQuickLookup:update()
             self.dict_frame,
         }
     }
-    UIManager.repaint_all = true
-    UIManager.partial_refresh = true
+    UIManager:setDirty("all", "partial")
 end
 
 function DictQuickLookup:isPrevDictAvaiable()
diff --git a/frontend/ui/widget/focusmanager.lua b/frontend/ui/widget/focusmanager.lua
index df70cdd78..a88200119 100644
--- a/frontend/ui/widget/focusmanager.lua
+++ b/frontend/ui/widget/focusmanager.lua
@@ -80,6 +80,7 @@ function FocusManager:onFocusMove(args)
             current_item:handleEvent(Event:new("Unfocus"))
             self.layout[self.selected.y][self.selected.x]:handleEvent(Event:new("Focus"))
             -- trigger a repaint (we need to be the registered widget!)
+            -- TODO: is this really needed?
             UIManager:setDirty(self.show_parent or self, "partial")
             break
         end
diff --git a/frontend/ui/widget/iconbutton.lua b/frontend/ui/widget/iconbutton.lua
index 5ac13f63e..f67afb267 100644
--- a/frontend/ui/widget/iconbutton.lua
+++ b/frontend/ui/widget/iconbutton.lua
@@ -43,16 +43,17 @@ end
 function IconButton:onTapClickButton()
     UIManager:scheduleIn(0.0, function()
         self.image.invert = true
-        UIManager.update_regions_func = function()
-            return {self[1].dimen}
-        end
-        UIManager:setDirty(self.show_parent, "partial")
+        UIManager:setDirty(self.show_parent, function()
+            return "partial", self[1].dimen
+        end)
     end)
     -- make sure button reacts before doing callback
     UIManager:scheduleIn(0.1, function()
         self.callback()
         self.image.invert = false
-        UIManager:setDirty(self.show_parent, "partial")
+        UIManager:setDirty(self.show_parent, function()
+            return "partial", self[1].dimen
+        end)
     end)
     return true
 end
diff --git a/frontend/ui/widget/inputdialog.lua b/frontend/ui/widget/inputdialog.lua
index 9b10e6517..a36d27470 100644
--- a/frontend/ui/widget/inputdialog.lua
+++ b/frontend/ui/widget/inputdialog.lua
@@ -116,8 +116,8 @@ function InputDialog:init()
         },
         self.dialog_frame,
     }
-    UIManager.repaint_all = true
-    UIManager.full_refresh = true
+    -- do a full refresh - is this really needed?
+    UIManager:setDirty("all", "full")
 end
 
 function InputDialog:onShowKeyboard()
diff --git a/frontend/ui/widget/inputtext.lua b/frontend/ui/widget/inputtext.lua
index ae7b6bc96..fc342317f 100644
--- a/frontend/ui/widget/inputtext.lua
+++ b/frontend/ui/widget/inputtext.lua
@@ -154,7 +154,9 @@ function InputText:addChar(char)
     table.insert(self.charlist, self.charpos, char)
     self.charpos = self.charpos + 1
     self:initTextBox(table.concat(self.charlist))
-    UIManager:setDirty(self.parent, "partial")
+    UIManager:setDirty(self.parent, function()
+        return "ui", self.dimen
+    end)
 end
 
 function InputText:delChar()
@@ -162,12 +164,14 @@ function InputText:delChar()
     self.charpos = self.charpos - 1
     table.remove(self.charlist, self.charpos)
     self:initTextBox(table.concat(self.charlist))
-    UIManager:setDirty(self.parent, "partial")
+    UIManager:setDirty(self.parent, "ui")
 end
 
 function InputText:clear()
     self:initTextBox("")
-    UIManager:setDirty(self.parent, "partial")
+    UIManager:setDirty(self.parent, function()
+        return "ui", self.dimen
+    end)
 end
 
 function InputText:getText()
@@ -176,7 +180,9 @@ end
 
 function InputText:setText(text)
     self:initTextBox(text)
-    UIManager:setDirty(self.parent, "partial")
+    UIManager:setDirty(self.parent, function()
+        return "partial", self.dimen
+    end)
 end
 
 return InputText
diff --git a/frontend/ui/widget/logindialog.lua b/frontend/ui/widget/logindialog.lua
index 1b147be66..006a1f5f4 100644
--- a/frontend/ui/widget/logindialog.lua
+++ b/frontend/ui/widget/logindialog.lua
@@ -87,8 +87,7 @@ function LoginDialog:init()
         },
         self.dialog_frame,
     }
-    UIManager.repaint_all = true
-    UIManager.full_refresh = true
+    UIManager:setDirty("all", "full")
 end
 
 function LoginDialog:getCredential()
diff --git a/frontend/ui/widget/menu.lua b/frontend/ui/widget/menu.lua
index 3b7cdfbe6..fa1cd9599 100644
--- a/frontend/ui/widget/menu.lua
+++ b/frontend/ui/widget/menu.lua
@@ -283,6 +283,7 @@ end
 function MenuItem:onTapSelect(arg, ges)
     local pos = self:getGesPosition(ges)
     self[1].invert = true
+    -- TODO: regional refresh
     UIManager:setDirty(self.show_parent, "partial")
     UIManager:scheduleIn(0.1, function()
         self[1].invert = false
@@ -295,6 +296,7 @@ end
 function MenuItem:onHoldSelect(arg, ges)
     local pos = self:getGesPosition(ges)
     self[1].invert = true
+    -- TODO: regional refresh
     UIManager:setDirty(self.show_parent, "partial")
     UIManager:scheduleIn(0.1, function()
         self[1].invert = false
@@ -650,7 +652,9 @@ function Menu:updateItems(select_number)
 
     -- nicolua
     -- FIXME: dirty hack to clear previous menus
-    UIManager:setDirty(self.show_parent or self)
+    -- TODO: regional refresh
+    UIManager:setDirty("all", "partial")
+    --UIManager:setDirty(self.show_parent or self, "partial")
 end
 
 --[[
diff --git a/frontend/ui/widget/multiinputdialog.lua b/frontend/ui/widget/multiinputdialog.lua
index 572c0f484..96a46d9e3 100644
--- a/frontend/ui/widget/multiinputdialog.lua
+++ b/frontend/ui/widget/multiinputdialog.lua
@@ -79,8 +79,7 @@ function MultiInputDialog:init()
         },
         self.dialog_frame,
     }
-    UIManager.repaint_all = true
-    UIManager.full_refresh = true
+    UIManager:setDirty("all", "full")
 end
 
 function MultiInputDialog:getFields()
diff --git a/frontend/ui/widget/scrolltextwidget.lua b/frontend/ui/widget/scrolltextwidget.lua
index fdc8b90df..28a86ee00 100644
--- a/frontend/ui/widget/scrolltextwidget.lua
+++ b/frontend/ui/widget/scrolltextwidget.lua
@@ -77,10 +77,9 @@ function ScrollTextWidget:onScrollText(arg, ges)
         self.text_widget:scrollUp()
         self:updateScrollBar(self.text_widget)
     end
-    UIManager.update_regions_func = function()
-        return {self.dimen}
-    end
-    UIManager:setDirty(self.dialog, "partial")
+    UIManager:setDirty(self.dialog, function()
+        return "partial", self.dimen
+    end)
 end
 
 return ScrollTextWidget
diff --git a/frontend/ui/widget/toggleswitch.lua b/frontend/ui/widget/toggleswitch.lua
index ee6004d82..b63a74702 100644
--- a/frontend/ui/widget/toggleswitch.lua
+++ b/frontend/ui/widget/toggleswitch.lua
@@ -144,10 +144,9 @@ function ToggleSwitch:onTapSelect(arg, gev)
     --]]
     self.config:onConfigChoose(self.values, self.name,
                     self.event, self.args, self.events, self.position)
-    UIManager.update_regions_func = function()
-        return {self.dimen}
-    end
-    UIManager:setDirty(self.config, "partial")
+    UIManager:setDirty(self.config, function()
+        return "partial", self.dimen
+    end)
     return true
 end
 
diff --git a/frontend/ui/widget/touchmenu.lua b/frontend/ui/widget/touchmenu.lua
index 37fe8af2f..7a75eece7 100644
--- a/frontend/ui/widget/touchmenu.lua
+++ b/frontend/ui/widget/touchmenu.lua
@@ -98,17 +98,18 @@ function TouchMenuItem:onTapSelect(arg, ges)
 
     UIManager:scheduleIn(0.0, function()
         self.item_frame.invert = true
-        UIManager.update_regions_func = function()
-            return {self.dimen}
-        end
-        UIManager:setDirty(self.show_parent, "partial")
+        UIManager:setDirty(self.show_parent, function()
+            return "partial", self.dimen
+        end)
     end)
     UIManager:scheduleIn(0.1, function()
         self.menu:onMenuSelect(self.item)
     end)
     UIManager:scheduleIn(0.5, function()
         self.item_frame.invert = false
-        UIManager:setDirty(self.show_parent, "partial")
+        UIManager:setDirty(self.show_parent, function()
+            return "partial", self.dimen
+        end)
     end)
     return true
 end
@@ -122,17 +123,18 @@ function TouchMenuItem:onHoldSelect(arg, ges)
 
     UIManager:scheduleIn(0.0, function()
         self.item_frame.invert = true
-        UIManager.update_regions_func = function()
-            return {self.dimen}
-        end
-        UIManager:setDirty(self.show_parent, "partial")
+        UIManager:setDirty(self.show_parent, function()
+            return "partial", self.dimen
+        end)
     end)
     UIManager:scheduleIn(0.1, function()
         self.menu:onMenuHold(self.item)
     end)
     UIManager:scheduleIn(0.5, function()
         self.item_frame.invert = false
-        UIManager:setDirty(self.show_parent, "partial")
+        UIManager:setDirty(self.show_parent, function()
+            return "partial", self.dimen
+        end)
     end)
     return true
 end
@@ -460,7 +462,9 @@ function TouchMenu:updateItems()
     self.time_info.text = os.date("%H:%M").." @ "..Device:getPowerDevice():getCapacity().."%"
     -- FIXME: this is a dirty hack to clear previous menus
     -- refer to issue #664 (in kindlepdfviewer)
-    UIManager.repaint_all = true
+    -- TODO: regional refresh
+    UIManager:setDirty("all", "partial")
+    --UIManager:setDirty(self.show_parent or self, "partial")
 end
 
 function TouchMenu:switchMenuTab(tab_num)
diff --git a/frontend/ui/widget/virtualkeyboard.lua b/frontend/ui/widget/virtualkeyboard.lua
index b0a8fe6b8..1cc861c4c 100644
--- a/frontend/ui/widget/virtualkeyboard.lua
+++ b/frontend/ui/widget/virtualkeyboard.lua
@@ -96,21 +96,22 @@ function VirtualKey:init()
 end
 
 function VirtualKey:update_keyboard()
-    UIManager.update_regions_func = function()
+    UIManager:setDirty(self.keyboard, function()
         DEBUG("update key region", self[1].dimen)
-        return {self[1].dimen}
-    end
-    UIManager:setDirty(self.keyboard, "partial")
+        return "ui", self[1].dimen
+    end)
 end
 
 function VirtualKey:update_keyboard_inputbox()
     local inputbox = self.keyboard.inputbox
-    UIManager.update_regions_func = function()
-        DEBUG("update keyboard and inputbox", self[1].dimen, inputbox.dimen)
-        return {self[1].dimen, inputbox.dimen}
-    end
-    UIManager:setDirty(inputbox, "partial")
-    UIManager:setDirty(self.keyboard, "partial")
+    UIManager:setDirty(self.keyboard, function()
+        DEBUG("update inputbox", inputbox.dimen)
+        return "ui", inputbox.dimen
+    end)
+    UIManager:setDirty(self.keyboard, function()
+        DEBUG("update keyboard", self[1].dimen)
+        return "ui", self[1].dimen
+    end)
 end
 
 function VirtualKey:onTapSelect()
@@ -318,8 +319,13 @@ function VirtualKeyboard:setLayout(key)
         if self.utf8mode then self.umlautmode = false end
     end
     self:initLayout()
-    UIManager.update_regions_func = nil
-    UIManager:setDirty(self, "partial")
+    UIManager:setDirty(self, function()
+        -- correct coordinates of keyboard
+        local dimen = self.dimen:copy()
+        dimen.y = Screen:getHeight() - dimen.h
+        DEBUG("update keyboard layout", dimen)
+        return "partial", dimen
+    end)
 end
 
 function VirtualKeyboard:addChar(key)
diff --git a/frontend/up_reg.list b/frontend/up_reg.list
new file mode 100644
index 000000000..77fddaf52
--- /dev/null
+++ b/frontend/up_reg.list
@@ -0,0 +1,19 @@
+./apps/reader/modules/readerfooter.lua:        UIManager.update_regions_func = function()
+./apps/reader/modules/readerhighlight.lua:        UIManager.update_regions_func = function()
+./ui/widget/button.lua:            UIManager.update_regions_func = function()
+./ui/widget/iconbutton.lua:        UIManager.update_regions_func = function()
+./ui/widget/dictquicklookup.lua:    UIManager.update_regions_func = function()
+./ui/widget/scrolltextwidget.lua:    UIManager.update_regions_func = function()
+./ui/widget/touchmenu.lua:        UIManager.update_regions_func = function()
+./ui/widget/touchmenu.lua:        UIManager.update_regions_func = function()
+./ui/widget/virtualkeyboard.lua:    UIManager.update_regions_func = function()
+./ui/widget/virtualkeyboard.lua:    UIManager.update_regions_func = function()
+./ui/widget/virtualkeyboard.lua:    UIManager.update_regions_func = nil
+./ui/widget/toggleswitch.lua:    UIManager.update_regions_func = function()
+./ui/widget/configdialog.lua:    UIManager.update_regions_func = function()
+./ui/widget/configdialog.lua:    UIManager.update_regions_func = function()
+./ui/uimanager.lua:    update_regions_func = nil,
+./ui/uimanager.lua:        if self.update_regions_func then
+./ui/uimanager.lua:            local update_regions = self.update_regions_func()
+./ui/uimanager.lua:            for _, update_region in ipairs(update_regions) do
+./ui/uimanager.lua:            self.update_regions_func = nil