diff --git a/app/image-viewer/buffer.py b/app/image-viewer/buffer.py
index d8b1e0d..9ea80b4 100644
--- a/app/image-viewer/buffer.py
+++ b/app/image-viewer/buffer.py
@@ -20,7 +20,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 from PyQt5 import QtCore
-from PyQt5.QtCore import QRect, Qt
+from PyQt5.QtCore import QRect
 from PyQt5.QtGui import QColor, QPixmap, QPainter
 from PyQt5.QtWidgets import QWidget
 from core.buffer import Buffer
diff --git a/app/pdf-viewer/buffer.py b/app/pdf-viewer/buffer.py
index 8de1513..28f4b85 100755
--- a/app/pdf-viewer/buffer.py
+++ b/app/pdf-viewer/buffer.py
@@ -21,7 +21,7 @@
 
 from PyQt5 import QtCore
 from PyQt5.QtCore import Qt, QRect, QEvent
-from PyQt5.QtGui import QColor, QPixmap, QImage, QFont, QCursor
+from PyQt5.QtGui import QColor, QPixmap, QImage, QFont
 from PyQt5.QtGui import QPainter
 from PyQt5.QtWidgets import QWidget
 from core.buffer import Buffer
@@ -737,7 +737,7 @@ class PdfViewerWidget(QWidget):
                 if len(bbox_list) >= 2:
                     tl_x, tl_y = 0, 0 # top left point
                     for index, bbox in enumerate(bbox_list[:-1]):
-                        if (tl_x == 0) or (tl_x == 0):
+                        if (tl_x == 0) or (tl_y == 0):
                             tl_x, tl_y = bbox[:2]
                         if bbox[0] > bbox_list[index + 1][2]:
                             br_x, br_y = bbox[2:] # bottom right
diff --git a/app/rss-reader/buffer.py b/app/rss-reader/buffer.py
index a7093f3..1e6bda6 100644
--- a/app/rss-reader/buffer.py
+++ b/app/rss-reader/buffer.py
@@ -20,10 +20,10 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 from PyQt5.QtCore import QUrl, Qt
-from PyQt5.QtGui import QColor, QPainter, QFont, QTextDocument
-from PyQt5.QtWidgets import QPushButton, QHBoxLayout, QWidget, QApplication, QWidget, QListWidget, QVBoxLayout, QLabel, QPushButton, QListWidgetItem, QStackedWidget, QSizePolicy
+from PyQt5.QtGui import QColor, QFont
+from PyQt5.QtWidgets import QPushButton, QHBoxLayout, QWidget, QWidget, QListWidget, QVBoxLayout, QLabel, QListWidgetItem, QStackedWidget
 from core.buffer import Buffer
-from PyQt5 import QtWidgets, QtCore
+from PyQt5 import QtCore
 from core.browser import BrowserView
 from core.utils import touch
 import feedparser
diff --git a/core/buffer.py b/core/buffer.py
index 39693e7..7330b56 100755
--- a/core/buffer.py
+++ b/core/buffer.py
@@ -117,14 +117,12 @@ qt_key_dict = {
     '''?''': Qt.Key_Question,
     '''"''': Qt.Key_QuoteDbl,
     '''`''': Qt.Key_QuoteLeft,
-    '''$''': Qt.Key_Dollar,
     '''%''': Qt.Key_Percent,
     '''^''': Qt.Key_AsciiCircum,
     '''&''': Qt.Key_Ampersand,
     '''*''': Qt.Key_Asterisk,
     '''~''': Qt.Key_AsciiTilde,
     '''!''': Qt.Key_Exclam,
-    '''/''': Qt.Key_Slash,
     '''\'''': Qt.Key_Apostrophe,
     '''SPC''': Qt.Key_Space,
     '''RET''': Qt.Key_Return,