Multiline-Icons should be treated as icons as well.

powerlevel9k.zsh-theme

@@ -68,6 +68,8 @@ case $POWERLEVEL9K_MODE in
       OK_ICON                        "\U2713" # ✓
       FAIL_ICON                      "\U2718" # ✘
       SYMFONY_ICON                   "SF"
+      MULTILINE_FIRST_PROMPT_PREFIX  "╭─"
+      MULTILINE_SECOND_PROMPT_PREFIX "╰─ "
       APPLE_ICON                     $'\UF8FF' # 
       FREEBSD_ICON                   $'\U1F608 ' # 😈
       LINUX_ICON                     $'\U1F427 ' # 🐧
@@ -105,6 +107,8 @@ case $POWERLEVEL9K_MODE in
       OK_ICON                        "\U2713" # ✓
       FAIL_ICON                      "\U2718" # ✘
       SYMFONY_ICON                   "SF"
+      MULTILINE_FIRST_PROMPT_PREFIX  "╭─"
+      MULTILINE_SECOND_PROMPT_PREFIX "╰─ "
       APPLE_ICON                     'OSX'
       FREEBSD_ICON                   'BSD'
       LINUX_ICON                     'Lx'
@@ -140,7 +144,7 @@ case $POWERLEVEL9K_MODE in
 esac
 
 if [[ "$POWERLEVEL9K_HIDE_BRANCH_ICON" == true ]]; then
-    $icons['VCS_BRANCH_ICON']=''
+    icons[VCS_BRANCH_ICON]=''
 fi
 
 function print_icon() {
@@ -643,11 +647,8 @@ powerlevel9k_init() {
   add-zsh-hook precmd vcs_info
 
   if [[ "$POWERLEVEL9K_PROMPT_ON_NEWLINE" == true ]]; then
-    [[ -n $POWERLEVEL9K_MULTILINE_FIRST_PROMPT_PREFIX ]] || POWERLEVEL9K_MULTILINE_FIRST_PROMPT_PREFIX="╭─"
-    [[ -n $POWERLEVEL9K_MULTILINE_SECOND_PROMPT_PREFIX ]] || POWERLEVEL9K_MULTILINE_SECOND_PROMPT_PREFIX="╰─ "
-
-    PROMPT="$POWERLEVEL9K_MULTILINE_FIRST_PROMPT_PREFIX%{%f%b%k%}"'$(build_left_prompt)'"
-$POWERLEVEL9K_MULTILINE_SECOND_PROMPT_PREFIX"
+    PROMPT="$(print_icon 'MULTILINE_FIRST_PROMPT_PREFIX')%{%f%b%k%}"'$(build_left_prompt)'"
+$(print_icon 'MULTILINE_SECOND_PROMPT_PREFIX')"
     # The right prompt should be on the same line as the first line of the left
     # prompt.  To do so, there is just a quite ugly workaround: Before zsh draws
     # the RPROMPT, we advise it, to go one line up. At the end of RPROMPT, we