diff --git a/NEWS.md b/NEWS.md
index a76900d..32dcba2 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,10 @@
 # New in 0.13
 
+- 0.13.3: the legacy string-key shim on `ImageViewGUI` now routes unknown
+  keys to the `extras::Dict{Symbol,Any}` field instead of throwing
+  `ArgumentError`. This restores the pre-0.13 pattern of using the GUI
+  handle as a scratch space for downstream-defined keys (with a depwarn).
+  `Base.haskey(::ImageViewGUI, ::AbstractString)` is also defined.
 - `imshow` now returns an `ImageDisplay` struct rather than a nested
   `Dict{String,Any}`. The nested GUI and ROI groupings are exposed as
   the structs `ImageViewGUI` (returned by `imshow_gui`) and `ImageROI`
diff --git a/Project.toml b/Project.toml
index 67f5dcc..09c32ea 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "ImageView"
 uuid = "86fae568-95e7-573e-a6b2-d8a6b900c9ef"
 author = ["Tim Holy <tim.holy@gmail.com", "Jared Wahlstrand <jwahlstrand@gmail.com>"]
-version = "0.13.2"
+version = "0.13.3"
 
 [deps]
 AxisArrays = "39de3d68-74b9-583c-8d2d-e117c070f3a9"
diff --git a/src/ImageView.jl b/src/ImageView.jl
index 66349a5..b3b27a3 100644
--- a/src/ImageView.jl
+++ b/src/ImageView.jl
@@ -20,6 +20,11 @@ export AnnotationText, AnnotationPoint, AnnotationPoints,
 export CLim, annotate!, annotations, canvasgrid, imshow, imshow!, imshow_gui, imlink,
        roi, scalebar, setup_contrast_popup!, slice2d
 
+# Public-but-not-exported types that downstream packages dispatch on.
+@static if VERSION >= v"1.11"
+    eval(Expr(:public, :ImageDisplay, :ImageViewGUI, :ImageROI))
+end
+
 const AbstractGray{T} = Color{T,1}
 const GrayLike = Union{AbstractGray,Number}
 const FixedColorant{T<:FixedPoint} = Colorant{T}
diff --git a/src/deprecated.jl b/src/deprecated.jl
index 54ba23f..b6c9897 100644
--- a/src/deprecated.jl
+++ b/src/deprecated.jl
@@ -66,14 +66,24 @@ function _legacy_get(g::ImageViewGUI, key::AbstractString)
     key == "hoverinfo"      && return getfield(g, :hoverinfo)
     key == "zoomregion_info" && return getfield(g, :zoomregion_info)
     key == "guidata"        && return getfield(g, :extras)[:guidata]
-    throw(KeyError(key))
+    # Pre-0.13 callers used the GUI Dict as scratch space for arbitrary keys
+    # (e.g. stashing a `zoom_region` observable). Route those through `extras`.
+    return getfield(g, :extras)[Symbol(key)]
 end
 function _legacy_set!(g::ImageViewGUI, key::AbstractString, value)
     key == "hoverinfo"       && (g.hoverinfo = value; return value)
     key == "zoomregion_info" && (g.zoomregion_info = value; return value)
     key == "players"         && (g.players = value; return value)
-    key == "guidata"         && (g.extras[:guidata] = value; return value)
-    throw(ArgumentError("cannot assign legacy key \"$key\" on ImageViewGUI"))
+    getfield(g, :extras)[Symbol(key)] = value
+    return value
+end
+
+Base.haskey(g::ImageViewGUI, key::AbstractString) =
+    _legacy_haskey_known(g, key) || haskey(getfield(g, :extras), Symbol(key))
+
+function _legacy_haskey_known(::ImageViewGUI, key::AbstractString)
+    return key in ("window", "vbox", "frame", "canvas", "status", "viewlabel",
+                   "players", "hoverinfo", "zoomregion_info", "guidata")
 end
 
 function _legacy_get(r::ImageROI, key::AbstractString)