diff --git a/src/calibre/gui2/tweak_book/editor/smarts/html.py b/src/calibre/gui2/tweak_book/editor/smarts/html.py
index 819ebfcd55..b137193bba 100644
--- a/src/calibre/gui2/tweak_book/editor/smarts/html.py
+++ b/src/calibre/gui2/tweak_book/editor/smarts/html.py
@@ -250,6 +250,7 @@ def ensure_not_within_tag_definition(cursor, forward=True):
 
     return False
 
+
 BLOCK_TAG_NAMES = frozenset((
     'address', 'article', 'aside', 'blockquote', 'center', 'dir', 'fieldset',
     'isindex', 'menu', 'noframes', 'hgroup', 'noscript', 'pre', 'section',
@@ -294,6 +295,7 @@ def set_style_property(tag, property_name, value, editor):
         d.setProperty(property_name, value)
         c.insertText('"%s"' % css(d))
 
+
 entity_pat = re.compile(r'&(#{0,1}[a-zA-Z0-9]{1,8});$')
 
 
@@ -700,6 +702,7 @@ class Smarts(NullSmarts):
         in_text = find_tag_definition(block, 0)[0] is None
 
         def append(text, start):
+            text = text.replace(PARAGRAPH_SEPARATOR, '\n')
             after = start + len(text)
             if start <= cend and cstart < after:
                 extra = after - (cend + 1)
@@ -715,9 +718,8 @@ class Smarts(NullSmarts):
             if not boundaries:
                 # Add the whole line
                 if in_text:
-                    text = block.text()
-                    if text:
-                        append(text, block.position())
+                    text = block.text() + '\n'
+                    append(text, block.position())
             else:
                 start = block.position()
                 c.setPosition(start)
@@ -733,11 +735,12 @@ class Smarts(NullSmarts):
                     c.setPosition(block.position() + boundaries[-1].offset + 1)
                     c.movePosition(c.EndOfBlock, c.KeepAnchor)
                     if c.hasSelection():
-                        append(c.selectedText(), c.anchor())
+                        append(c.selectedText() + '\n', c.anchor())
             block = block.next()
         s, e = find_text_in_chunks(pat, chunks)
         return s != -1 and e != -1, s, e
 
+
 if __name__ == '__main__':  # {{{
     from calibre.gui2.tweak_book.editor.widget import launch_editor
     if sys.argv[-1].endswith('.html'):