diff --git a/release/bash/gupload b/release/bash/gupload
index 24d71d2..7ad962d 100755
--- a/release/bash/gupload
+++ b/release/bash/gupload
@@ -972,28 +972,60 @@ fi
 else
 "${QUIET:-_print_center}" "normal" " No Refresh token given, follow below steps to generate.. " "-"&&unset refresh_token_value_check_refresh_token
 fi
+server_string_check_refresh_token='Now go back to command line..'
+server_port_check_refresh_token='8079'
+while :;do
+: "$((server_port_check_refresh_token+=1))"
+if [ "$server_port_check_refresh_token" -gt 8130 ];then
+"${QUIET:-_print_center}" "normal" "Error: No open ports found ( 8080 to 8130 )." "-"
+return 1
+fi
+{ curl -Is "http://localhost:$server_port_check_refresh_token"&&continue;}||break
+done
+if command -v python 1>/dev/null&&python -V|grep -q 'Python 3';then
+python <<EOF 1>"$TMPFILE.code" 2>&1&
+from http.server import BaseHTTPRequestHandler, HTTPServer
+
+class handler(BaseHTTPRequestHandler):
+    def do_GET(self):
+        self.send_response(200)
+        self.end_headers()
+        if '/?code' in self.path:
+            message = '$server_string_check_refresh_token'
+            self.wfile.write(bytes(message, "utf8"))
+
+with HTTPServer(('', $server_port_check_refresh_token), handler) as server:
+    server.serve_forever()
+EOF
+_tmp_server_pid="$!"
+elif command -v nc 1>/dev/null;then
+printf "%b" "HTTP/1.1 200 OK\nContent-Length: $(printf "%s" "$server_string_check_refresh_token"|wc -c)\n\n$server_string_check_refresh_token"|nc -c -l -p "$server_port_check_refresh_token" 1>"$TMPFILE.code" 2>&1&
+_tmp_server_pid="$!"
+else
+"${QUIET:-_print_center}" "normal" " Error: neither netcat (nc) nor python3 is installed. It is required to required a http server which is used in fetching authorization code. Install and proceed." "-"
+return 1
+fi
+code_challenge_check_refresh_token="$(_epoch)authorization_code"
 [ -z "$refresh_token_value_check_refresh_token" ]&&{
-printf "\n"&&"${QUIET:-_print_center}" "normal" "Visit the below URL, tap on allow and then enter the code obtained" " "
-URL="https://accounts.google.com/o/oauth2/auth?client_id=$CLIENT_ID&redirect_uri=$REDIRECT_URI&scope=$SCOPE&response_type=code&prompt=consent"
+printf "\n"&&"${QUIET:-_print_center}" "normal" "Visit the below URL, follow the instructions and then come back to commandline" " "
+URL="https://accounts.google.com/o/oauth2/auth?client_id=$CLIENT_ID&redirect_uri=$REDIRECT_URI%3A$server_port_check_refresh_token&scope=$SCOPE&response_type=code&code_challenge_method=plain&code_challenge=$code_challenge_check_refresh_token"
 printf "\n%s\n" "$URL"
-unset AUTHORIZATION_CODE authorization_code AUTHORIZATION_CODE_VALID response
-until [ -n "$AUTHORIZATION_CODE" ]&&[ -n "$AUTHORIZATION_CODE_VALID" ];do
-[ -n "$AUTHORIZATION_CODE" ]&&{
-if _assert_regex "$authorization_code_regex" "$AUTHORIZATION_CODE";then
-AUTHORIZATION_CODE_VALID="true"&&continue
-else
-"${QUIET:-_print_center}" "normal" " Invalid CODE given, try again.. " "-"&&unset AUTHORIZATION_CODE authorization_code
+"${QUIET:-_print_center}" "normal" " Press enter if you have completed the process in browser" "-"
+read -r _
+kill "$_tmp_server_pid"
+if ! authorization_code="$(grep -m1 'GET.*code.*HTTP/1.1' <"$TMPFILE.code"|sed -e 's/.*GET.*code=//' -e 's/\&.*//')"&&_assert_regex "$authorization_code_regex" "$authorization_code";then
+"${QUIET:-_print_center}" "normal" " Code was not fetched properly , here is some info that maybe helpful.. " "-"
+"${QUIET:-_print_center}" "normal" " Code that was grabbed: $authorization_code " "-"
+printf "Output of http server:\n"
+cat "$TMPFILE.code"
+(rm -f "$TMPFILE.code"&)
+return 1
 fi
-}
-{ [ -z "$authorization_code" ]&&printf "\n"&&"${QUIET:-_print_center}" "normal" " Enter the authorization code " "-";}||_clear_line 1
-printf -- "-> \033[?7l"
-read -r AUTHORIZATION_CODE&&authorization_code=1
-printf '\033[?7h'
-done
-response_check_refresh_token="$(curl --compressed "$CURL_PROGRESS" -X POST \
---data "code=$AUTHORIZATION_CODE&client_id=$CLIENT_ID&client_secret=$CLIENT_SECRET&redirect_uri=$REDIRECT_URI&grant_type=authorization_code" "$TOKEN_URL")"||:
+(rm -f "$TMPFILE.code"&)
+response_check_refresh_token="$(_curl --compressed "$CURL_PROGRESS" -X POST \
+--data "code=$authorization_code&client_id=$CLIENT_ID&client_secret=$CLIENT_SECRET&redirect_uri=$REDIRECT_URI%3A$server_port_check_refresh_token&grant_type=authorization_code&code_verifier=$code_challenge_check_refresh_token" "$TOKEN_URL")"||:
 _clear_line 1 1>&2
-refresh_token_value_check_refresh_token="$(printf "%s\n" "$response_check_refresh_token"|_json_value refresh_token 1 1)"||{ printf "%s\n" "Error: Cannot fetch refresh token, make sure the authorization code was correct."&&return 1;}
+refresh_token_value_check_refresh_token="$(printf "%s\n" "$response_check_refresh_token"|_json_value refresh_token 1 1)"||{ printf "%s\n" "Error: Cannot fetch refresh token, make sure the authorization code was correct."&&printf "%s\n" "$response_check_refresh_token"&&return 1;}
 _set_value direct REFRESH_TOKEN "$refresh_token_value_check_refresh_token"
 { _check_access_token "$account_name_check_refresh_token" skip_check "$response_check_refresh_token"&&_update_config "$refresh_token_name_check_refresh_token" "$refresh_token_value_check_refresh_token" "$CONFIG";}||return 1
 }
diff --git a/release/sh/gupload b/release/sh/gupload
index e238a30..f9def7c 100755
--- a/release/sh/gupload
+++ b/release/sh/gupload
@@ -945,28 +945,60 @@ fi
 else
 "${QUIET:-_print_center}" "normal" " No Refresh token given, follow below steps to generate.. " "-"&&unset refresh_token_value_check_refresh_token
 fi
+server_string_check_refresh_token='Now go back to command line..'
+server_port_check_refresh_token='8079'
+while :;do
+: "$((server_port_check_refresh_token+=1))"
+if [ "$server_port_check_refresh_token" -gt 8130 ];then
+"${QUIET:-_print_center}" "normal" "Error: No open ports found ( 8080 to 8130 )." "-"
+return 1
+fi
+{ curl -Is "http://localhost:$server_port_check_refresh_token"&&continue;}||break
+done
+if command -v python 1>/dev/null&&python -V|grep -q 'Python 3';then
+python <<EOF 1>"$TMPFILE.code" 2>&1&
+from http.server import BaseHTTPRequestHandler, HTTPServer
+
+class handler(BaseHTTPRequestHandler):
+    def do_GET(self):
+        self.send_response(200)
+        self.end_headers()
+        if '/?code' in self.path:
+            message = '$server_string_check_refresh_token'
+            self.wfile.write(bytes(message, "utf8"))
+
+with HTTPServer(('', $server_port_check_refresh_token), handler) as server:
+    server.serve_forever()
+EOF
+_tmp_server_pid="$!"
+elif command -v nc 1>/dev/null;then
+printf "%b" "HTTP/1.1 200 OK\nContent-Length: $(printf "%s" "$server_string_check_refresh_token"|wc -c)\n\n$server_string_check_refresh_token"|nc -c -l -p "$server_port_check_refresh_token" 1>"$TMPFILE.code" 2>&1&
+_tmp_server_pid="$!"
+else
+"${QUIET:-_print_center}" "normal" " Error: neither netcat (nc) nor python3 is installed. It is required to required a http server which is used in fetching authorization code. Install and proceed." "-"
+return 1
+fi
+code_challenge_check_refresh_token="$(_epoch)authorization_code"
 [ -z "$refresh_token_value_check_refresh_token" ]&&{
-printf "\n"&&"${QUIET:-_print_center}" "normal" "Visit the below URL, tap on allow and then enter the code obtained" " "
-URL="https://accounts.google.com/o/oauth2/auth?client_id=$CLIENT_ID&redirect_uri=$REDIRECT_URI&scope=$SCOPE&response_type=code&prompt=consent"
+printf "\n"&&"${QUIET:-_print_center}" "normal" "Visit the below URL, follow the instructions and then come back to commandline" " "
+URL="https://accounts.google.com/o/oauth2/auth?client_id=$CLIENT_ID&redirect_uri=$REDIRECT_URI%3A$server_port_check_refresh_token&scope=$SCOPE&response_type=code&code_challenge_method=plain&code_challenge=$code_challenge_check_refresh_token"
 printf "\n%s\n" "$URL"
-unset AUTHORIZATION_CODE authorization_code AUTHORIZATION_CODE_VALID response
-until [ -n "$AUTHORIZATION_CODE" ]&&[ -n "$AUTHORIZATION_CODE_VALID" ];do
-[ -n "$AUTHORIZATION_CODE" ]&&{
-if _assert_regex "$authorization_code_regex" "$AUTHORIZATION_CODE";then
-AUTHORIZATION_CODE_VALID="true"&&continue
-else
-"${QUIET:-_print_center}" "normal" " Invalid CODE given, try again.. " "-"&&unset AUTHORIZATION_CODE authorization_code
+"${QUIET:-_print_center}" "normal" " Press enter if you have completed the process in browser" "-"
+read -r _
+kill "$_tmp_server_pid"
+if ! authorization_code="$(grep -m1 'GET.*code.*HTTP/1.1' <"$TMPFILE.code"|sed -e 's/.*GET.*code=//' -e 's/\&.*//')"&&_assert_regex "$authorization_code_regex" "$authorization_code";then
+"${QUIET:-_print_center}" "normal" " Code was not fetched properly , here is some info that maybe helpful.. " "-"
+"${QUIET:-_print_center}" "normal" " Code that was grabbed: $authorization_code " "-"
+printf "Output of http server:\n"
+cat "$TMPFILE.code"
+(rm -f "$TMPFILE.code"&)
+return 1
 fi
-}
-{ [ -z "$authorization_code" ]&&printf "\n"&&"${QUIET:-_print_center}" "normal" " Enter the authorization code " "-";}||_clear_line 1
-printf -- "-> \033[?7l"
-read -r AUTHORIZATION_CODE&&authorization_code=1
-printf '\033[?7h'
-done
-response_check_refresh_token="$(curl --compressed "$CURL_PROGRESS" -X POST \
---data "code=$AUTHORIZATION_CODE&client_id=$CLIENT_ID&client_secret=$CLIENT_SECRET&redirect_uri=$REDIRECT_URI&grant_type=authorization_code" "$TOKEN_URL")"||:
+(rm -f "$TMPFILE.code"&)
+response_check_refresh_token="$(_curl --compressed "$CURL_PROGRESS" -X POST \
+--data "code=$authorization_code&client_id=$CLIENT_ID&client_secret=$CLIENT_SECRET&redirect_uri=$REDIRECT_URI%3A$server_port_check_refresh_token&grant_type=authorization_code&code_verifier=$code_challenge_check_refresh_token" "$TOKEN_URL")"||:
 _clear_line 1 1>&2
-refresh_token_value_check_refresh_token="$(printf "%s\n" "$response_check_refresh_token"|_json_value refresh_token 1 1)"||{ printf "%s\n" "Error: Cannot fetch refresh token, make sure the authorization code was correct."&&return 1;}
+refresh_token_value_check_refresh_token="$(printf "%s\n" "$response_check_refresh_token"|_json_value refresh_token 1 1)"||{ printf "%s\n" "Error: Cannot fetch refresh token, make sure the authorization code was correct."&&printf "%s\n" "$response_check_refresh_token"&&return 1;}
 _set_value direct REFRESH_TOKEN "$refresh_token_value_check_refresh_token"
 { _check_access_token "$account_name_check_refresh_token" skip_check "$response_check_refresh_token"&&_update_config "$refresh_token_name_check_refresh_token" "$refresh_token_value_check_refresh_token" "$CONFIG";}||return 1
 }
diff --git a/src/common/auth-utils.sh b/src/common/auth-utils.sh
index 7338fe1..0afdccd 100644
--- a/src/common/auth-utils.sh
+++ b/src/common/auth-utils.sh
@@ -336,30 +336,74 @@ _check_refresh_token() {
             "${QUIET:-_print_center}" "normal" " No Refresh token given, follow below steps to generate.. " "-" && unset refresh_token_value_check_refresh_token
         fi
 
+        server_string_check_refresh_token='Now go back to command line..'
+        server_port_check_refresh_token='8079'
+        # run a loop until an open port has been found
+        # check for 50 ports
+        while :; do
+            : "$((server_port_check_refresh_token += 1))"
+            if [ "${server_port_check_refresh_token}" -gt 8130 ]; then
+                "${QUIET:-_print_center}" "normal" "Error: No open ports found ( 8080 to 8130 )." "-"
+                return 1
+            fi
+            { curl -Is "http://localhost:${server_port_check_refresh_token}" && continue; } || break
+        done
+
+        # https://docs.python.org/3/library/http.server.html
+        if command -v python 1> /dev/null && python -V | grep -q 'Python 3'; then
+            python << EOF 1> "${TMPFILE}.code" 2>&1 &
+from http.server import BaseHTTPRequestHandler, HTTPServer
+
+class handler(BaseHTTPRequestHandler):
+    def do_GET(self):
+        self.send_response(200)
+        self.end_headers()
+        if '/?code' in self.path:
+            message = '${server_string_check_refresh_token}'
+            self.wfile.write(bytes(message, "utf8"))
+
+with HTTPServer(('', ${server_port_check_refresh_token}), handler) as server:
+    server.serve_forever()
+EOF
+            _tmp_server_pid="${!}"
+        elif command -v nc 1> /dev/null; then
+            # https://stackoverflow.com/a/58436505
+            printf "%b" "HTTP/1.1 200 OK\nContent-Length: $(printf "%s" "${server_string_check_refresh_token}" | wc -c)\n\n${server_string_check_refresh_token}" | nc -c -l -p "${server_port_check_refresh_token}" 1> "${TMPFILE}.code" 2>&1 &
+            _tmp_server_pid="${!}"
+        else
+            "${QUIET:-_print_center}" "normal" " Error: neither netcat (nc) nor python3 is installed. It is required to required a http server which is used in fetching authorization code. Install and proceed." "-"
+            return 1
+        fi
+
+        # https://developers.google.com/identity/protocols/oauth2/native-app#obtainingaccesstokens
+        code_challenge_check_refresh_token="$(_epoch)authorization_code"
         [ -z "${refresh_token_value_check_refresh_token}" ] && {
-            printf "\n" && "${QUIET:-_print_center}" "normal" "Visit the below URL, tap on allow and then enter the code obtained" " "
-            URL="https://accounts.google.com/o/oauth2/auth?client_id=${CLIENT_ID}&redirect_uri=${REDIRECT_URI}&scope=${SCOPE}&response_type=code&prompt=consent"
+            printf "\n" && "${QUIET:-_print_center}" "normal" "Visit the below URL, follow the instructions and then come back to commandline" " "
+            URL="https://accounts.google.com/o/oauth2/auth?client_id=${CLIENT_ID}&redirect_uri=${REDIRECT_URI}%3A${server_port_check_refresh_token}&scope=${SCOPE}&response_type=code&code_challenge_method=plain&code_challenge=${code_challenge_check_refresh_token}"
             printf "\n%s\n" "${URL}"
-            unset AUTHORIZATION_CODE authorization_code AUTHORIZATION_CODE_VALID response
-            until [ -n "${AUTHORIZATION_CODE}" ] && [ -n "${AUTHORIZATION_CODE_VALID}" ]; do
-                [ -n "${AUTHORIZATION_CODE}" ] && {
-                    if _assert_regex "${authorization_code_regex}" "${AUTHORIZATION_CODE}"; then
-                        AUTHORIZATION_CODE_VALID="true" && continue
-                    else
-                        "${QUIET:-_print_center}" "normal" " Invalid CODE given, try again.. " "-" && unset AUTHORIZATION_CODE authorization_code
-                    fi
-                }
-                { [ -z "${authorization_code}" ] && printf "\n" && "${QUIET:-_print_center}" "normal" " Enter the authorization code " "-"; } || _clear_line 1
-                printf -- "-> \033[?7l"
-                read -r AUTHORIZATION_CODE && authorization_code=1
-                printf '\033[?7h'
-            done
-            response_check_refresh_token="$(curl --compressed "${CURL_PROGRESS}" -X POST \
-                --data "code=${AUTHORIZATION_CODE}&client_id=${CLIENT_ID}&client_secret=${CLIENT_SECRET}&redirect_uri=${REDIRECT_URI}&grant_type=authorization_code" "${TOKEN_URL}")" || :
+
+            "${QUIET:-_print_center}" "normal" " Press enter if you have completed the process in browser" "-"
+            read -r _
+            kill "${_tmp_server_pid}"
+
+            if ! authorization_code="$(grep -m1 'GET.*code.*HTTP/1.1' < "${TMPFILE}.code" | sed -e 's/.*GET.*code=//' -e 's/\&.*//')" &&
+                _assert_regex "${authorization_code_regex}" "${authorization_code}"; then
+                "${QUIET:-_print_center}" "normal" " Code was not fetched properly , here is some info that maybe helpful.. " "-"
+                "${QUIET:-_print_center}" "normal" " Code that was grabbed: ${authorization_code} " "-"
+                printf "Output of http server:\n"
+                cat "${TMPFILE}.code"
+                (rm -f "${TMPFILE}.code" &)
+                return 1
+            fi
+            (rm -f "${TMPFILE}.code" &)
+
+            # https://developers.google.com/identity/protocols/oauth2/native-app#handlingresponse
+            response_check_refresh_token="$(_curl --compressed "${CURL_PROGRESS}" -X POST \
+                --data "code=${authorization_code}&client_id=${CLIENT_ID}&client_secret=${CLIENT_SECRET}&redirect_uri=${REDIRECT_URI}%3A${server_port_check_refresh_token}&grant_type=authorization_code&code_verifier=${code_challenge_check_refresh_token}" "${TOKEN_URL}")" || :
             _clear_line 1 1>&2
 
             refresh_token_value_check_refresh_token="$(printf "%s\n" "${response_check_refresh_token}" | _json_value refresh_token 1 1)" ||
-                { printf "%s\n" "Error: Cannot fetch refresh token, make sure the authorization code was correct." && return 1; }
+                { printf "%s\n" "Error: Cannot fetch refresh token, make sure the authorization code was correct." && printf "%s\n" "${response_check_refresh_token}" && return 1; }
 
             _set_value direct REFRESH_TOKEN "${refresh_token_value_check_refresh_token}"
             { _check_access_token "${account_name_check_refresh_token}" skip_check "${response_check_refresh_token}" &&