diff --git a/lib/functions/configuration/interactive.sh b/lib/functions/configuration/interactive.sh
index f06b1f12f8..5d6f551251 100644
--- a/lib/functions/configuration/interactive.sh
+++ b/lib/functions/configuration/interactive.sh
@@ -14,6 +14,15 @@ function interactive_config_prepare_terminal() {
 	export backtitle="Armbian building script, https://www.armbian.com | https://docs.armbian.com | (c) 2013-2023 Igor Pecovnik "
 }
 
+function interactive_finish() {
+	unset TTY_X
+	unset TTY_Y
+	unset options
+	unset DIALOG_EXIT_CODE
+	unset WIP_STATE
+	unset SHOW_WARNING
+}
+
 function interactive_config_ask_kernel() {
 	interactive_config_ask_kernel_only
 	interactive_config_ask_kernel_configure
diff --git a/lib/functions/configuration/main-config.sh b/lib/functions/configuration/main-config.sh
index 553d030a68..3daee3bac4 100644
--- a/lib/functions/configuration/main-config.sh
+++ b/lib/functions/configuration/main-config.sh
@@ -278,7 +278,7 @@ function do_main_configuration() {
 	[[ -z $UBOOT_USE_GCC ]] && exit_with_error "Error in configuration: UBOOT_USE_GCC is unset"
 	[[ -z $KERNEL_USE_GCC ]] && exit_with_error "Error in configuration: KERNEL_USE_GCC is unset"
 
-	BOOTCONFIG_VAR_NAME=BOOTCONFIG_${BRANCH^^}
+	declare BOOTCONFIG_VAR_NAME="BOOTCONFIG_${BRANCH^^}"
 	[[ -n ${!BOOTCONFIG_VAR_NAME} ]] && BOOTCONFIG=${!BOOTCONFIG_VAR_NAME}
 	[[ -z $LINUXCONFIG ]] && LINUXCONFIG="linux-${LINUXFAMILY}-${BRANCH}"
 	[[ -z $BOOTPATCHDIR ]] && BOOTPATCHDIR="u-boot-$LINUXFAMILY"
diff --git a/lib/functions/main/config-prepare.sh b/lib/functions/main/config-prepare.sh
index 2d99d839d2..9a26b5d180 100644
--- a/lib/functions/main/config-prepare.sh
+++ b/lib/functions/main/config-prepare.sh
@@ -57,8 +57,9 @@ function prepare_and_config_main_build_single() {
 	declare -A dict_all_board_types=() dict_all_board_source_files=()                                           # dictionaries
 	get_list_of_all_buildable_boards arr_all_board_names "" dict_all_board_types dict_all_board_source_files "" # invoke
 
-	BOARD_TYPE="${dict_all_board_types["${BOARD}"]}"
-	BOARD_SOURCE_FILES="${dict_all_board_source_files["${BOARD}"]}"
+	declare BOARD_TYPE="${dict_all_board_types["${BOARD}"]}"
+	declare BOARD_SOURCE_FILES="${dict_all_board_source_files["${BOARD}"]}"
+	declare BOARD_SOURCE_FILE
 
 	declare -a sourced_board_configs=()
 	for BOARD_SOURCE_FILE in ${BOARD_SOURCE_FILES}; do # No quotes, so expand the space-delimited list
@@ -92,6 +93,8 @@ function prepare_and_config_main_build_single() {
 
 	interactive_config_ask_standard_or_minimal
 
+	interactive_finish # cleans up vars
+
 	#prevent conflicting setup
 	if [[ $BUILD_DESKTOP == "yes" ]]; then
 		BUILD_MINIMAL=no