diff --git a/src/common.cpp b/src/common.cpp
index 040a22d9d..0c052282f 100644
--- a/src/common.cpp
+++ b/src/common.cpp
@@ -1002,7 +1002,6 @@ static void escape_string_script(const wchar_t *orig_in, size_t in_len, wcstring
                 case L'|':
                 case L';':
                 case L'"':
-                case L'%':
                 case L'~': {
                     if (!no_tilde || c != L'~') {
                         need_escape = 1;
@@ -1316,12 +1315,6 @@ static bool unescape_string_internal(const wchar_t *const input, const size_t in
                     }
                     break;
                 }
-                case L'%': {
-                    if (unescape_special && (input_position == 0)) {
-                        to_append_or_none = PROCESS_EXPAND;
-                    }
-                    break;
-                }
                 case L'*': {
                     if (unescape_special) {
                         // In general, this is ANY_STRING. But as a hack, if the last appended char
diff --git a/src/expand.cpp b/src/expand.cpp
index 194b4b941..631c6638a 100644
--- a/src/expand.cpp
+++ b/src/expand.cpp
@@ -590,6 +590,7 @@ static bool expand_pid(const wcstring &instr_with_sep, expand_flags_t flags,
 
     // We know we are a process expansion now.
     assert(in[0] == PROCESS_EXPAND);
+    return true;
 
     if (flags & EXPAND_FOR_COMPLETIONS) {
         if (wcsncmp(in + 1, SELF_STR, wcslen(in + 1)) == 0) {
diff --git a/src/highlight.cpp b/src/highlight.cpp
index 1c91172d7..c0366c7d5 100644
--- a/src/highlight.cpp
+++ b/src/highlight.cpp
@@ -120,7 +120,6 @@ bool is_potential_path(const wcstring &potential_path_fragment, const wcstring_l
     for (size_t i = 0; i < path_with_magic.size(); i++) {
         wchar_t c = path_with_magic.at(i);
         switch (c) {
-            case PROCESS_EXPAND:
             case VARIABLE_EXPAND:
             case VARIABLE_EXPAND_SINGLE:
             case BRACKET_BEGIN:
@@ -535,8 +534,7 @@ static void color_argument_internal(const wcstring &buffstr,
                 } else {
                     // Not a backslash.
                     switch (c) {
-                        case L'~':
-                        case L'%': {
+                        case L'~': {
                             if (in_pos == 0) {
                                 colors[in_pos] = highlight_spec_operator;
                             }