diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9e6e395..fe7dab6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,15 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [1.6.8] - 2026-05-07
+
+### Fixed
+- `zsh/.zshrc`: gate `fzf-tab` tmux popup mode (`fzf-command ftb-tmux-popup`)
+  behind a runtime tmux version check (`>= 3.2`). On hosts with tmux < 3.2
+  (e.g. Ubuntu 20.04 system tmux 3.0a) the `ftb-tmux-popup` script called
+  `tmux popup` which does not exist, producing an `unknown command: popup`
+  error on every TAB completion. The guard falls back to inline fzf silently.
+
 ## [1.6.7] - 2026-05-07
 
 ### Fixed
diff --git a/VERSION b/VERSION
index 400084b..d8c5e72 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-1.6.7
+1.6.8
diff --git a/zsh/.zshrc b/zsh/.zshrc
index afd6c7b..a16de5d 100644
--- a/zsh/.zshrc
+++ b/zsh/.zshrc
@@ -80,6 +80,10 @@ zstyle ':completion:*' menu no
 zstyle ':fzf-tab:complete:cd:*' fzf-preview 'eza --color=always -1 $realpath 2>/dev/null || ls --color=always -1 $realpath 2>/dev/null'
 zstyle ':fzf-tab:*' switch-group '<' '>'
 zstyle ':fzf-tab:*' popup-min-size 30 8
+# display-popup requires tmux >= 3.2; fall back to inline fzf on older hosts
+if [[ -n "$TMUX_PANE" ]] && tmux -V 2>/dev/null | awk '{exit !($2+0 >= 3.2)}'; then
+  zstyle ':fzf-tab:*' fzf-command ftb-tmux-popup
+fi
 
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