diff --git a/Makefile b/Makefile
index 440697ea5..39cbc82ba 100644
--- a/Makefile
+++ b/Makefile
@@ -250,14 +250,15 @@ pbupdate: all
 	file $(INSTALL_DIR)/koreader/luajit | grep ARM || exit 1
 	# remove old package if any
 	rm -f $(PB_PACKAGE)
-	# Pocketbook launching script
+	# Pocketbook launching scripts
 	mkdir -p $(INSTALL_DIR)/applications
 	mkdir -p $(INSTALL_DIR)/system/bin
-	mkdir -p $(INSTALL_DIR)/system/config
-
 	cp $(POCKETBOOK_DIR)/koreader.app $(INSTALL_DIR)/applications
 	cp $(POCKETBOOK_DIR)/koreader.app $(INSTALL_DIR)/system/bin
 	cp -rfL $(INSTALL_DIR)/koreader $(INSTALL_DIR)/applications
+	find $(INSTALL_DIR)/applications/koreader \
+		-type f \( -name "*.gif" -o -name "*.html" -o -name "*.md" -o -name "*.txt" \) \
+		-exec rm -vf {} \;
 	# create new package
 	cd $(INSTALL_DIR) && \
 		zip -9 -r \
diff --git a/frontend/apps/reader/modules/readerfont.lua b/frontend/apps/reader/modules/readerfont.lua
index 02bd422fc..b35e13d04 100644
--- a/frontend/apps/reader/modules/readerfont.lua
+++ b/frontend/apps/reader/modules/readerfont.lua
@@ -397,7 +397,7 @@ If that font happens to be part of this list already, it will be used first.]]),
 end
 
 -- Default sample file
-local FONT_TEST_DEFAULT_SAMPLE_PATH = "frontend/ui/elements/font-test-sample-default.html"
+local FONT_TEST_DEFAULT_SAMPLE_PATH = "frontend/ui/elements/font-test-sample-default.template"
 -- Users can set their own sample file, that will be used if found
 local FONT_TEST_USER_SAMPLE_PATH = require("datastorage"):getSettingsDir() .. "/font-test-sample.html"
 -- This document will be generated in the home or default directory
diff --git a/frontend/ui/elements/file_ext_assoc.lua b/frontend/ui/elements/file_ext_assoc.lua
index 4c042e461..692423611 100644
--- a/frontend/ui/elements/file_ext_assoc.lua
+++ b/frontend/ui/elements/file_ext_assoc.lua
@@ -1,7 +1,13 @@
 local Device = require("device")
-local DocumentRegistry = require("document/documentregistry")
 local _ = require("gettext")
 
+local function getSupportedExtensions()
+    local t = require("document/documentregistry"):getExtensions()
+    t["sh"] = nil
+    t["py"] = nil
+    return t
+end
+
 local ExtAssoc = {
     assoc = G_reader_settings:readSetting("file_ext_assoc") or {},
 }
@@ -10,14 +16,14 @@ function ExtAssoc:commit()
     G_reader_settings:saveSetting("file_ext_assoc", self.assoc):flush()
     -- Translate the boolean map back to map of providers the OS backend can inquire further
     local t = {}
-    for k, v in pairs(DocumentRegistry:getExtensions()) do
+    for k, v in pairs(getSupportedExtensions()) do
         if self.assoc[k] then t[k] = v end
     end
     Device:associateFileExtensions(t)
 end
 
 function ExtAssoc:setAll(state)
-    for k, dummy in pairs(DocumentRegistry:getExtensions()) do
+    for k, dummy in pairs(getSupportedExtensions()) do
         self:setOne(k, state)
     end
     self:commit()
@@ -47,7 +53,7 @@ function ExtAssoc:getSettingsMenuTable()
             separator = true,
         },
     }
-    local exts = DocumentRegistry:getExtensions()
+    local exts = getSupportedExtensions()
     local keys = {}
     for k, dummy in pairs(exts) do
         table.insert(keys, k)
diff --git a/frontend/ui/elements/font-test-sample-default.html b/frontend/ui/elements/font-test-sample-default.template
similarity index 100%
rename from frontend/ui/elements/font-test-sample-default.html
rename to frontend/ui/elements/font-test-sample-default.template