diff --git a/onionshare_gui/__init__.py b/onionshare_gui/__init__.py
index 23d8dd3d..73e0d305 100644
--- a/onionshare_gui/__init__.py
+++ b/onionshare_gui/__init__.py
@@ -63,7 +63,7 @@ def main():
     common.define_css()
 
     # Display OnionShare banner
-    print("OnionShare {0:s} | https://onionshare.org/".format(common.version))
+    print(f"OnionShare {common.version} | https://onionshare.org/")
 
     # Allow Ctrl-C to smoothly quit the program instead of throwing an exception
     # https://stackoverflow.com/questions/42814093/how-to-handle-ctrlc-in-python-app-with-pyqt
@@ -124,10 +124,10 @@ def main():
         valid = True
         for filename in filenames:
             if not os.path.isfile(filename) and not os.path.isdir(filename):
-                Alert(common, "{0:s} is not a valid file.".format(filename))
+                Alert(common, f"{filename} is not a valid file.")
                 valid = False
             if not os.access(filename, os.R_OK):
-                Alert(common, "{0:s} is not a readable file.".format(filename))
+                Alert(common, f"{filename} is not a readable file.")
                 valid = False
         if not valid:
             sys.exit()
diff --git a/onionshare_gui/mode/__init__.py b/onionshare_gui/mode/__init__.py
index 04709dc2..7180f24f 100644
--- a/onionshare_gui/mode/__init__.py
+++ b/onionshare_gui/mode/__init__.py
@@ -119,18 +119,10 @@ class Mode(QtWidgets.QWidget):
         if not seconds:
             seconds = "0"
         result = (
-            ("{0}{1}, ".format(days, strings._("days_first_letter")) if days else "")
-            + (
-                "{0}{1}, ".format(hours, strings._("hours_first_letter"))
-                if hours
-                else ""
-            )
-            + (
-                "{0}{1}, ".format(minutes, strings._("minutes_first_letter"))
-                if minutes
-                else ""
-            )
-            + "{0}{1}".format(seconds, strings._("seconds_first_letter"))
+            (f"{days}{strings._('days_first_letter')}, " if days else "")
+            + (f"{hours}{strings._('hours_first_letter')}, " if hours else "")
+            + (f"{minutes}{strings._('minutes_first_letter')}, " if minutes else "")
+            + f"{seconds}{strings._('seconds_first_letter')}"
         )
 
         return result
diff --git a/onionshare_gui/mode/file_selection.py b/onionshare_gui/mode/file_selection.py
index c505dc03..62cff0a7 100644
--- a/onionshare_gui/mode/file_selection.py
+++ b/onionshare_gui/mode/file_selection.py
@@ -171,7 +171,7 @@ class FileList(QtWidgets.QListWidget):
         if event.mimeData().hasUrls:
             self.setStyleSheet(self.common.css["share_file_list_drag_enter"])
             count = len(event.mimeData().urls())
-            self.drop_count.setText("+{}".format(count))
+            self.drop_count.setText(f"+{count}")
 
             size_hint = self.drop_count.sizeHint()
             self.drop_count.setGeometry(
diff --git a/onionshare_gui/mode/history.py b/onionshare_gui/mode/history.py
index 85eec7e4..67b23072 100644
--- a/onionshare_gui/mode/history.py
+++ b/onionshare_gui/mode/history.py
@@ -181,9 +181,7 @@ class ReceiveHistoryItemFile(QtWidgets.QWidget):
         super(ReceiveHistoryItemFile, self).__init__()
         self.common = common
 
-        self.common.log(
-            "ReceiveHistoryItemFile", "__init__", "filename: {}".format(filename)
-        )
+        self.common.log("ReceiveHistoryItemFile", "__init__", f"filename: {filename}")
 
         self.filename = filename
         self.dir = None
@@ -265,7 +263,7 @@ class ReceiveHistoryItemFile(QtWidgets.QWidget):
 
         # Windows
         elif self.common.platform == "Windows":
-            subprocess.Popen(["explorer", "/select,{}".format(abs_filename)])
+            subprocess.Popen(["explorer", f"/select,{abs_filename}"])
 
 
 class ReceiveHistoryItem(HistoryItem):
@@ -409,7 +407,7 @@ class IndividualFileHistoryItem(HistoryItem):
         self.timestamp_label.setStyleSheet(
             self.common.css["history_individual_file_timestamp_label"]
         )
-        self.path_label = QtWidgets.QLabel("{}".format(self.path))
+        self.path_label = QtWidgets.QLabel(self.path)
         self.status_code_label = QtWidgets.QLabel()
 
         # Progress bar
@@ -437,7 +435,7 @@ class IndividualFileHistoryItem(HistoryItem):
 
         # Is a status code already sent?
         if "status_code" in data:
-            self.status_code_label.setText("{}".format(data["status_code"]))
+            self.status_code_label.setText(str(data["status_code"]))
             if data["status_code"] >= 200 and data["status_code"] < 300:
                 self.status_code_label.setStyleSheet(
                     self.common.css["history_individual_file_status_code_label_2xx"]
@@ -649,7 +647,7 @@ class History(QtWidgets.QWidget):
         """
         Add a new item.
         """
-        self.common.log("History", "add", "id: {}, item: {}".format(id, item))
+        self.common.log("History", "add", f"id: {id}, item: {item}")
 
         # Hide empty, show not empty
         self.empty.hide()
@@ -699,9 +697,7 @@ class History(QtWidgets.QWidget):
             image = self.common.get_resource_path("images/history_completed_none.png")
         else:
             image = self.common.get_resource_path("images/history_completed.png")
-        self.completed_label.setText(
-            '<img src="{0:s}" /> {1:d}'.format(image, self.completed_count)
-        )
+        self.completed_label.setText(f'<img src="{image}" /> {self.completed_count}')
         self.completed_label.setToolTip(
             strings._("history_completed_tooltip").format(self.completed_count)
         )
@@ -716,7 +712,7 @@ class History(QtWidgets.QWidget):
             image = self.common.get_resource_path("images/history_in_progress.png")
 
         self.in_progress_label.setText(
-            '<img src="{0:s}" /> {1:d}'.format(image, self.in_progress_count)
+            f'<img src="{image}" /> {self.in_progress_count}'
         )
         self.in_progress_label.setToolTip(
             strings._("history_in_progress_tooltip").format(self.in_progress_count)
@@ -731,9 +727,7 @@ class History(QtWidgets.QWidget):
         else:
             image = self.common.get_resource_path("images/history_requests.png")
 
-        self.requests_label.setText(
-            '<img src="{0:s}" /> {1:d}'.format(image, self.requests_count)
-        )
+        self.requests_label.setText(f'<img src="{image}" /> {self.requests_count}')
         self.requests_label.setToolTip(
             strings._("history_requests_tooltip").format(self.requests_count)
         )
@@ -777,7 +771,7 @@ class ToggleHistory(QtWidgets.QPushButton):
         if increment and not self.history_widget.isVisible():
             self.indicator_count += 1
 
-        self.indicator_label.setText("{}".format(self.indicator_count))
+        self.indicator_label.setText(str(self.indicator_count))
 
         if self.indicator_count == 0:
             self.indicator_label.hide()
diff --git a/onionshare_gui/onionshare_gui.py b/onionshare_gui/onionshare_gui.py
index 4639ea13..299130a9 100644
--- a/onionshare_gui/onionshare_gui.py
+++ b/onionshare_gui/onionshare_gui.py
@@ -655,22 +655,15 @@ class OnionShareGui(QtWidgets.QMainWindow):
                 )
 
             if event["type"] == Web.REQUEST_OTHER:
-                if event["path"] != "/favicon.ico" and event[
-                    "path"
-                ] != "/{}/shutdown".format(mode.web.shutdown_password):
-                    self.status_bar.showMessage(
-                        "{0:s}: {1:s}".format(
-                            strings._("other_page_loaded"), event["path"]
-                        )
-                    )
+                if (
+                    event["path"] != "/favicon.ico"
+                    and event["path"] != f"/{mode.web.shutdown_password}/shutdown"
+                ):
+                    self.status_bar.showMessage(f"{strings._("other_page_loaded")}: {event["path"]}")
 
             if event["type"] == Web.REQUEST_INVALID_PASSWORD:
                 self.status_bar.showMessage(
-                    "[#{0:d}] {1:s}: {2:s}".format(
-                        mode.web.invalid_passwords_count,
-                        strings._("incorrect_password"),
-                        event["data"],
-                    )
+                    f"[#{mode.web.invalid_passwords_count}] {strings._('incorrect_password')}: {event['data']}"
                 )
 
         mode.timer_callback()
diff --git a/onionshare_gui/server_status.py b/onionshare_gui/server_status.py
index 4ce1f5d2..5732ce91 100644
--- a/onionshare_gui/server_status.py
+++ b/onionshare_gui/server_status.py
@@ -540,9 +540,7 @@ class ServerStatus(QtWidgets.QWidget):
         Returns the OnionShare URL.
         """
         if self.common.settings.get("public_mode"):
-            url = "http://{0:s}".format(self.app.onion_host)
+            url = f"http://{self.app.onion_host}"
         else:
-            url = "http://onionshare:{0:s}@{1:s}".format(
-                self.web.password, self.app.onion_host
-            )
+            url = f"http://onionshare:{self.web.password}@{self.app.onion_host}"
         return url
diff --git a/onionshare_gui/settings_dialog.py b/onionshare_gui/settings_dialog.py
index 503e53a0..4c03bd23 100644
--- a/onionshare_gui/settings_dialog.py
+++ b/onionshare_gui/settings_dialog.py
@@ -672,7 +672,7 @@ class SettingsDialog(QtWidgets.QDialog):
             strings._("gui_settings_button_cancel")
         )
         self.cancel_button.clicked.connect(self.cancel_clicked)
-        version_label = QtWidgets.QLabel("OnionShare {0:s}".format(self.common.version))
+        version_label = QtWidgets.QLabel(f"OnionShare {self.common.version}")
         version_label.setStyleSheet(self.common.css["settings_version"])
         self.help_button = QtWidgets.QPushButton(strings._("gui_settings_button_help"))
         self.help_button.clicked.connect(self.help_clicked)
@@ -1040,7 +1040,7 @@ class SettingsDialog(QtWidgets.QDialog):
             self.common.log(
                 "SettingsDialog",
                 "data_dir_button_clicked",
-                "selected dir: {}".format(selected_dir),
+                f"selected dir: {selected_dir}",
             )
             self.data_dir_lineedit.setText(selected_dir)
 
@@ -1255,9 +1255,7 @@ class SettingsDialog(QtWidgets.QDialog):
                     self.common.log(
                         "SettingsDialog",
                         "save_clicked",
-                        "Onion done rebooting, connected to Tor: {}".format(
-                            self.onion.connected_to_tor
-                        ),
+                        f"Onion done rebooting, connected to Tor: {self.onion.connected_to_tor}",
                     )
 
                     if self.onion.is_authenticated() and not tor_con.wasCanceled():
@@ -1473,9 +1471,7 @@ class SettingsDialog(QtWidgets.QDialog):
 
     def _tor_status_update(self, progress, summary):
         self.tor_status.setText(
-            "<strong>{}</strong><br>{}% {}".format(
-                strings._("connecting_to_tor"), progress, summary
-            )
+            f"<strong>{strings._('connecting_to_tor')}</strong><br>{progress}% {summary}"
         )
         self.qtapp.processEvents()
         if "Done" in summary:
diff --git a/onionshare_gui/tor_connection_dialog.py b/onionshare_gui/tor_connection_dialog.py
index 58fc01d0..3d20cd22 100644
--- a/onionshare_gui/tor_connection_dialog.py
+++ b/onionshare_gui/tor_connection_dialog.py
@@ -86,7 +86,7 @@ class TorConnectionDialog(QtWidgets.QProgressDialog):
     def _tor_status_update(self, progress, summary):
         self.setValue(int(progress))
         self.setLabelText(
-            "<strong>{}</strong><br>{}".format(strings._("connecting_to_tor"), summary)
+            f"<strong>{strings._("connecting_to_tor")}</strong><br>{summary}"
         )
 
     def _connected_to_tor(self):
@@ -112,7 +112,7 @@ class TorConnectionDialog(QtWidgets.QProgressDialog):
             # Display the exception in an alert box
             Alert(
                 self.common,
-                "{}\n\n{}".format(msg, strings._("gui_tor_connection_error_settings")),
+                f"{msg}\n\n{strings._("gui_tor_connection_error_settings")}",
                 QtWidgets.QMessageBox.Warning,
             )
 
@@ -162,7 +162,7 @@ class TorConnectionThread(QtCore.QThread):
 
         except Exception as e:
             self.common.log(
-                "TorConnectionThread", "run", "caught exception: {}".format(e.args[0])
+                "TorConnectionThread", "run", f"caught exception: {e.args[0]}"
             )
             self.error_connecting_to_tor.emit(str(e.args[0]))
 
diff --git a/onionshare_gui/update_checker.py b/onionshare_gui/update_checker.py
index a8bd7979..2b0edec9 100644
--- a/onionshare_gui/update_checker.py
+++ b/onionshare_gui/update_checker.py
@@ -71,7 +71,7 @@ class UpdateChecker(QtCore.QObject):
         self.config = config
 
     def check(self, force=False, config=False):
-        self.common.log("UpdateChecker", "check", "force={}".format(force))
+        self.common.log("UpdateChecker", "check", f"force={force}")
         # Load the settings
         settings = Settings(self.common, config)
         settings.load()
@@ -100,9 +100,7 @@ class UpdateChecker(QtCore.QObject):
             # Download the latest-version file over Tor
             try:
                 # User agent string includes OnionShare version and platform
-                user_agent = "OnionShare {}, {}".format(
-                    self.common.version, self.common.platform
-                )
+                user_agent = f"OnionShare {self.common.version}, {self.common.platform}"
 
                 # If the update is forced, add '?force=1' to the URL, to more
                 # accurately measure daily users
@@ -118,9 +116,7 @@ class UpdateChecker(QtCore.QObject):
                     onion_domain = "elx57ue5uyfplgva.onion"
 
                 self.common.log(
-                    "UpdateChecker",
-                    "check",
-                    "loading http://{}{}".format(onion_domain, path),
+                    "UpdateChecker", "check", f"loading http://{onion_domain}{path}"
                 )
 
                 (socks_address, socks_port) = self.onion.get_tor_socks_port()
@@ -130,9 +126,9 @@ class UpdateChecker(QtCore.QObject):
                 s.settimeout(15)  # 15 second timeout
                 s.connect((onion_domain, 80))
 
-                http_request = "GET {} HTTP/1.0\r\n".format(path)
-                http_request += "Host: {}\r\n".format(onion_domain)
-                http_request += "User-Agent: {}\r\n".format(user_agent)
+                http_request = f"GET {path} HTTP/1.0\r\n"
+                http_request += f"Host: {onion_domain}\r\n"
+                http_request += f"User-Agent: {user_agent}\r\n"
                 http_request += "\r\n"
                 s.sendall(http_request.encode("utf-8"))
 
@@ -146,11 +142,11 @@ class UpdateChecker(QtCore.QObject):
                 self.common.log(
                     "UpdateChecker",
                     "check",
-                    "latest OnionShare version: {}".format(latest_version),
+                    f"latest OnionShare version: {latest_version}",
                 )
 
             except Exception as e:
-                self.common.log("UpdateChecker", "check", "{}".format(e))
+                self.common.log("UpdateChecker", "check", str(e))
                 self.update_error.emit()
                 raise UpdateCheckerCheckError
 
@@ -174,9 +170,7 @@ class UpdateChecker(QtCore.QObject):
             settings.save()
 
             # Do we need to update?
-            update_url = "https://github.com/micahflee/onionshare/releases/tag/v{}".format(
-                latest_version
-            )
+            update_url = f"https://github.com/micahflee/onionshare/releases/tag/v{latest_version}"
             installed_version = self.common.version
             if installed_version < latest_version:
                 self.update_available.emit(
@@ -217,7 +211,7 @@ class UpdateThread(QtCore.QThread):
             u.check(config=self.config, force=self.force)
         except Exception as e:
             # If update check fails, silently ignore
-            self.common.log("UpdateThread", "run", "{}".format(e))
+            self.common.log("UpdateThread", "run", str(e))
             pass
 
     def _update_available(self, update_url, installed_version, latest_version):