misc cleanups for RTL merge

src/pyj/read_book/flow_mode.pyj

@@ -121,6 +121,7 @@ def flow_onwheel(evt):
 def goto_boundary(dir):
     scroll_viewport.scroll_to(scroll_viewport.x(), 0 if dir is DIRECTION.Up else document_height())
     get_boss().report_human_scroll()
+    return False
 
 
 @check_for_scroll_end_and_report
@@ -132,6 +133,7 @@ def scroll_by_page(direction, flip_if_rtl_page_progression):
     # the progression direction.
     return flip_if_rtl_page_progression and rtl_page_progression()
 
+
 def scroll_to_extend_annotation(backward, horizontal, by_page):
     direction = -1 if backward else 1
     h = line_height()

src/pyj/read_book/paged_mode.pyj

@@ -584,7 +584,7 @@ onwheel = wheel_handler.onwheel.bind(wheel_handler)
 
 
 def scroll_by_page(backward, by_screen, flip_if_rtl_page_progression):
-    if (flip_if_rtl_page_progression and rtl_page_progression()):
+    if flip_if_rtl_page_progression and rtl_page_progression():
         backward = not backward
 
     if by_screen:

src/pyj/read_book/settings.pyj

@@ -92,9 +92,9 @@ def apply_colors():
     # it is not displayed properly when scrolling unless overflow:visible is set,
     # but this causes scrollbars to appear.
     # Force disable scrollbars in Chrome, Safari, and Firefox to address this side effect.
-    text += '\nhtml::-webkit-scrollbar, body::-webkit-scrollbar { display: none }'
-    text += '\nhtml { scrollbar-width: none; }'
-    text += '\nbody { scrollbar-width: none; }'
+    text += '\nhtml::-webkit-scrollbar, body::-webkit-scrollbar { display: none !important }'
+    # for firefox: https://developer.mozilla.org/en-US/docs/Web/CSS/scrollbar-width
+    text += '\nhtml, body { scrollbar-width: none !important }'
 
     ss.textContent = text
 

src/pyj/read_book/touch.pyj

@@ -248,7 +248,7 @@ class BookTouchHandler(TouchHandler):
                     if gesture.viewport_y < min(100, scroll_viewport.height() / 4):
                         gesture.type = 'show-chrome'
                     else:
-                        # Calibre's default, books that go left to right.
+                        # default, books that go left to right.
                         if ltr_page_progression():
                             if gesture.viewport_x < min(100, scroll_viewport.width() / 4):
                                 gesture.type = 'prev-page'