diff --git a/engine/src/flutter/shell/platform/glfw/text_input_plugin.cc b/engine/src/flutter/shell/platform/glfw/text_input_plugin.cc
index 760bea2ce8..496b9e0abc 100644
--- a/engine/src/flutter/shell/platform/glfw/text_input_plugin.cc
+++ b/engine/src/flutter/shell/platform/glfw/text_input_plugin.cc
@@ -187,9 +187,13 @@ void TextInputPlugin::HandleMethodCall(
                     "Selection base/extent values invalid.");
       return;
     }
-    active_model_->SetEditingState(selection_base->value.GetInt(),
-                                   selection_extent->value.GetInt(),
-                                   text->value.GetString());
+    // Flutter uses -1/-1 for invalid; translate that to 0/0 for the model.
+    int base = selection_base->value.GetInt();
+    int extent = selection_extent->value.GetInt();
+    if (base == -1 && extent == -1) {
+      base = extent = 0;
+    }
+    active_model_->SetEditingState(base, extent, text->value.GetString());
   } else {
     result->NotImplemented();
     return;
diff --git a/engine/src/flutter/shell/platform/linux/fl_text_input_plugin.cc b/engine/src/flutter/shell/platform/linux/fl_text_input_plugin.cc
index a50c60b804..f62203f71b 100644
--- a/engine/src/flutter/shell/platform/linux/fl_text_input_plugin.cc
+++ b/engine/src/flutter/shell/platform/linux/fl_text_input_plugin.cc
@@ -4,12 +4,12 @@
 
 #include "flutter/shell/platform/linux/fl_text_input_plugin.h"
 
+#include <gtk/gtk.h>
+
 #include "flutter/shell/platform/common/cpp/text_input_model.h"
 #include "flutter/shell/platform/linux/public/flutter_linux/fl_json_method_codec.h"
 #include "flutter/shell/platform/linux/public/flutter_linux/fl_method_channel.h"
 
-#include <gtk/gtk.h>
-
 static constexpr char kChannelName[] = "flutter/textinput";
 
 static constexpr char kBadArgumentsError[] = "Bad Arguments";
@@ -190,6 +190,10 @@ static FlMethodResponse* set_editing_state(FlTextInputPlugin* self,
       fl_value_get_int(fl_value_lookup_string(args, kSelectionBaseKey));
   int64_t selection_extent =
       fl_value_get_int(fl_value_lookup_string(args, kSelectionExtentKey));
+  // Flutter uses -1/-1 for invalid; translate that to 0/0 for the model.
+  if (selection_base == -1 && selection_extent == -1) {
+    selection_base = selection_extent = 0;
+  }
 
   self->text_model->SetEditingState(selection_base, selection_extent, text);
 
diff --git a/engine/src/flutter/shell/platform/windows/text_input_plugin.cc b/engine/src/flutter/shell/platform/windows/text_input_plugin.cc
index 46849b0672..43bdc50be4 100644
--- a/engine/src/flutter/shell/platform/windows/text_input_plugin.cc
+++ b/engine/src/flutter/shell/platform/windows/text_input_plugin.cc
@@ -189,9 +189,13 @@ void TextInputPlugin::HandleMethodCall(
                     "Selection base/extent values invalid.");
       return;
     }
-    active_model_->SetEditingState(selection_base->value.GetInt(),
-                                   selection_extent->value.GetInt(),
-                                   text->value.GetString());
+    // Flutter uses -1/-1 for invalid; translate that to 0/0 for the model.
+    int base = selection_base->value.GetInt();
+    int extent = selection_extent->value.GetInt();
+    if (base == -1 && extent == -1) {
+      base = extent = 0;
+    }
+    active_model_->SetEditingState(base, extent, text->value.GetString());
   } else {
     result->NotImplemented();
     return;