diff --git a/oh-my-zsh.sh b/oh-my-zsh.sh
index 3e547d358..7d820bbfa 100644
--- a/oh-my-zsh.sh
+++ b/oh-my-zsh.sh
@@ -110,9 +110,14 @@ if [[ -z "$ZSH_COMPDUMP" ]]; then
   ZSH_COMPDUMP="${ZDOTDIR:-$HOME}/.zcompdump-${SHORT_HOST}-${ZSH_VERSION}"
 fi
 
-# Construct zcompdump OMZ metadata
+# Construct zcompdump OMZ metadata. fpath is deduplicated (preserving
+# first-occurrence order) before comparison so that sessions which
+# differ only in duplicate counts produce identical metadata. Order is
+# preserved because `compinit` resolves colliding completion files by
+# first-occurrence in fpath, so two fpaths with the same entries in a
+# different order can legitimately produce different completions.
 zcompdump_revision="#omz revision: $(builtin cd -q "$ZSH"; git rev-parse HEAD 2>/dev/null)"
-zcompdump_fpath="#omz fpath: $fpath"
+zcompdump_fpath="#omz fpath: ${${(@u)fpath}}"
 
 # Delete the zcompdump file if OMZ zcompdump metadata changed
 if ! command grep -q -Fx "$zcompdump_revision" "$ZSH_COMPDUMP" 2>/dev/null \