diff --git a/qt/aqt/deckoptions.py b/qt/aqt/deckoptions.py
index 2499bdcc8..276fe067a 100644
--- a/qt/aqt/deckoptions.py
+++ b/qt/aqt/deckoptions.py
@@ -4,6 +4,7 @@
 from __future__ import annotations
 
 import aqt
+from aqt import gui_hooks
 from aqt.qt import *
 from aqt.utils import addCloseShortcut, disable_help_button, restoreGeom, saveGeom
 from aqt.webview import AnkiWebView
@@ -38,7 +39,11 @@ class DeckOptionsDialog(QDialog):
         self.setLayout(layout)
 
         deck_id = self.mw.col.decks.get_current_id()
-        self.web.eval(f"anki.deckConfig(document.getElementById('main'), {deck_id});")
+        self.web.eval(
+            f"""const $deckOptions = anki.deckConfig(
+            document.getElementById('main'), {deck_id});"""
+        )
+        gui_hooks.deck_options_did_load(self)
 
     def reject(self) -> None:
         self.web = None
diff --git a/qt/tools/genhooks_gui.py b/qt/tools/genhooks_gui.py
index 3d611a988..346ba9c25 100644
--- a/qt/tools/genhooks_gui.py
+++ b/qt/tools/genhooks_gui.py
@@ -218,8 +218,8 @@ hooks = [
                 content.stats += "\n<div>my html</div>"
         """,
     ),
-    # Deck options
-    ###################
+    # Deck options (legacy screen)
+    ###############################
     Hook(
         name="deck_conf_did_setup_ui_form",
         args=["deck_conf: aqt.deckconf.DeckConf"],
@@ -287,6 +287,15 @@ hooks = [
         ],
         doc="Called before config group is renamed",
     ),
+    # Deck options (new screen)
+    ############################
+    Hook(
+        name="deck_options_did_load",
+        args=[
+            "deck_options: aqt.deckoptions.DeckOptionsDialog",
+        ],
+        doc="Can be used to inject extra options into the config screen",
+    ),
     # Filtered deck options
     ###################
     Hook(
diff --git a/ts/deckconfig/Addons.svelte b/ts/deckconfig/Addons.svelte
new file mode 100644
index 000000000..0cb69b9af
--- /dev/null
+++ b/ts/deckconfig/Addons.svelte
@@ -0,0 +1,21 @@
+<!--
+Copyright: Ankitects Pty Ltd and contributors
+License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
+-->
+<script lang="ts">
+    // import * as tr from "lib/i18n";
+    import type { DeckConfigState } from "./lib";
+
+    export let state: DeckConfigState;
+    let components = state.addonComponents;
+</script>
+
+{#if $components.length}
+    <div>
+        <h2>Add-ons</h2>
+
+        {#each $components as addon}
+            <svelte:component this={addon.component} {state} {...addon} />
+        {/each}
+    </div>
+{/if}
diff --git a/ts/deckconfig/BUILD.bazel b/ts/deckconfig/BUILD.bazel
index 4c464a618..1f3c69437 100644
--- a/ts/deckconfig/BUILD.bazel
+++ b/ts/deckconfig/BUILD.bazel
@@ -65,6 +65,7 @@ ts_library(
         "//ts:image_module_support",
         "//ts/lib",
         "//ts/lib:backend_proto",
+        "//ts/sveltelib",
         "@npm//lodash-es",
         "@npm//svelte",
     ],
diff --git a/ts/deckconfig/ConfigEditor.svelte b/ts/deckconfig/ConfigEditor.svelte
index c01f1420b..c540d27d4 100644
--- a/ts/deckconfig/ConfigEditor.svelte
+++ b/ts/deckconfig/ConfigEditor.svelte
@@ -8,6 +8,7 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
     import ReviewOptions from "./ReviewOptions.svelte";
     import LapseOptions from "./LapseOptions.svelte";
     import GeneralOptions from "./GeneralOptions.svelte";
+    import Addons from "./Addons.svelte";
     import type { DeckConfigState } from "./lib";
 
     export let state: DeckConfigState;
@@ -29,4 +30,5 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
     <ReviewOptions {state} />
     <LapseOptions {state} />
     <GeneralOptions {state} />
+    <Addons {state} />
 </div>
diff --git a/ts/deckconfig/DeckConfigPage.svelte b/ts/deckconfig/DeckConfigPage.svelte
index 596ef2624..3762f0cf1 100644
--- a/ts/deckconfig/DeckConfigPage.svelte
+++ b/ts/deckconfig/DeckConfigPage.svelte
@@ -8,8 +8,26 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
     import type { DeckConfigState } from "./lib";
     import { onMount, onDestroy } from "svelte";
     import { registerShortcut } from "lib/shortcuts";
+    import type { Writable } from "svelte/store";
+    import HtmlAddon from "./HtmlAddon.svelte";
 
     export let state: DeckConfigState;
+    let addons = state.addonComponents;
+
+    export function auxData(): Writable<Record<string, unknown>> {
+        return state.currentAuxData;
+    }
+
+    export function addHtmlAddon(html: string, mounted: () => void): void {
+        $addons = [
+            ...$addons,
+            {
+                component: HtmlAddon,
+                html,
+                mounted,
+            },
+        ];
+    }
 
     let registerCleanup: () => void;
     onMount(() => {
diff --git a/ts/deckconfig/HtmlAddon.svelte b/ts/deckconfig/HtmlAddon.svelte
new file mode 100644
index 000000000..70a8578b7
--- /dev/null
+++ b/ts/deckconfig/HtmlAddon.svelte
@@ -0,0 +1,14 @@
+<!--
+Copyright: Ankitects Pty Ltd and contributors
+License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
+-->
+<script lang="typescript">
+    import { onMount } from "svelte";
+
+    export let html: string;
+    export let mounted: () => void;
+
+    onMount(mounted);
+</script>
+
+{@html html}
diff --git a/ts/deckconfig/index.ts b/ts/deckconfig/index.ts
index db4de5fae..58695377c 100644
--- a/ts/deckconfig/index.ts
+++ b/ts/deckconfig/index.ts
@@ -9,14 +9,14 @@ import DeckConfigPage from "./DeckConfigPage.svelte";
 export async function deckConfig(
     target: HTMLDivElement,
     deckId: number
-): Promise<void> {
+): Promise<DeckConfigPage> {
     checkNightMode();
     await setupI18n({
         modules: [ModuleName.SCHEDULING, ModuleName.ACTIONS, ModuleName.DECK_CONFIG],
     });
     const info = await getDeckConfigInfo(deckId);
     const state = new DeckConfigState(deckId, info);
-    new DeckConfigPage({
+    return new DeckConfigPage({
         target,
         props: { state },
     });
diff --git a/ts/deckconfig/lib.test.ts b/ts/deckconfig/lib.test.ts
index 39db17e22..be129a521 100644
--- a/ts/deckconfig/lib.test.ts
+++ b/ts/deckconfig/lib.test.ts
@@ -33,6 +33,8 @@ const exampleData = {
                     leechAction: "LEECH_ACTION_TAG_ONLY",
                     leechThreshold: 8,
                     capAnswerTimeToSecs: 60,
+                    other:
+                        "eyJuZXciOnsic2VwYXJhdGUiOnRydWV9LCJyZXYiOnsiZnV6eiI6MC4wNSwibWluU3BhY2UiOjF9fQ==",
                 },
             },
             useCount: 1,
@@ -276,3 +278,54 @@ test("saving", () => {
     expect(out.removedConfigIds).toStrictEqual([1618570764780]);
     expect(out.configs.map((c) => c.name)).toStrictEqual(["Default"]);
 });
+
+test("aux data", () => {
+    const state = startingState();
+    expect(get(state.currentAuxData)).toStrictEqual({});
+    state.currentAuxData.update((val) => {
+        return { ...val, hello: "world" };
+    });
+
+    // check default
+    state.setCurrentIndex(0);
+    expect(get(state.currentAuxData)).toStrictEqual({
+        new: {
+            separate: true,
+        },
+        rev: {
+            fuzz: 0.05,
+            minSpace: 1,
+        },
+    });
+    state.currentAuxData.update((val) => {
+        return { ...val, defaultAddition: true };
+    });
+
+    // ensure changes serialize
+    const out = state.dataForSaving(true);
+    expect(out.configs.length).toBe(2);
+    const json = out.configs.map(
+        (c) =>
+            JSON.parse(new TextDecoder().decode((c.config as any).other)) as Record<
+                string,
+                unknown
+            >
+    );
+    expect(json).toStrictEqual([
+        // other deck comes first
+        {
+            hello: "world",
+        },
+        // default is selected, so comes last
+        {
+            defaultAddition: true,
+            new: {
+                separate: true,
+            },
+            rev: {
+                fuzz: 0.05,
+                minSpace: 1,
+            },
+        },
+    ]);
+});
diff --git a/ts/deckconfig/lib.ts b/ts/deckconfig/lib.ts
index 7e69eb1f0..0a639ef3b 100644
--- a/ts/deckconfig/lib.ts
+++ b/ts/deckconfig/lib.ts
@@ -10,6 +10,7 @@ import { postRequest } from "lib/postrequest";
 import { Writable, writable, get, Readable, readable } from "svelte/store";
 import { isEqual, cloneDeep } from "lodash-es";
 import * as tr from "lib/i18n";
+import type { DynamicSvelteComponent } from "sveltelib/dynamicComponent";
 
 export async function getDeckConfigInfo(
     deckId: number
@@ -50,10 +51,12 @@ export interface ConfigListEntry {
 type ConfigInner = pb.BackendProto.DeckConfig.Config;
 export class DeckConfigState {
     readonly currentConfig: Writable<ConfigInner>;
+    readonly currentAuxData: Writable<Record<string, unknown>>;
     readonly configList: Readable<ConfigListEntry[]>;
     readonly parentLimits: Readable<ParentLimits>;
     readonly currentDeck: pb.BackendProto.DeckConfigsForUpdate.CurrentDeck;
     readonly defaults: ConfigInner;
+    readonly addonComponents: Writable<DynamicSvelteComponent[]>;
 
     private targetDeckId: number;
     private configs: ConfigWithCount[];
@@ -69,8 +72,9 @@ export class DeckConfigState {
         this.currentDeck = data.currentDeck as pb.BackendProto.DeckConfigsForUpdate.CurrentDeck;
         this.defaults = data.defaults!.config! as ConfigInner;
         this.configs = data.allConfig.map((config) => {
+            const configInner = config.config as pb.BackendProto.DeckConfig;
             return {
-                config: config.config as pb.BackendProto.DeckConfig,
+                config: configInner,
                 useCount: config.useCount!,
             };
         });
@@ -83,6 +87,7 @@ export class DeckConfigState {
         // selected one at display time
         this.configs[this.selectedIdx].useCount -= 1;
         this.currentConfig = writable(this.getCurrentConfig());
+        this.currentAuxData = writable(this.getCurrentAuxData());
         this.configList = readable(this.getConfigList(), (set) => {
             this.configListSetter = set;
             return;
@@ -92,6 +97,7 @@ export class DeckConfigState {
             return;
         });
         this.schemaModified = data.schemaModified;
+        this.addonComponents = writable([]);
 
         // create a temporary subscription to force our setters to be set immediately,
         // so unit tests don't get stale results
@@ -100,6 +106,7 @@ export class DeckConfigState {
 
         // update our state when the current config is changed
         this.currentConfig.subscribe((val) => this.onCurrentConfigChanged(val));
+        this.currentAuxData.subscribe((val) => this.onCurrentAuxDataChanged(val));
     }
 
     setCurrentIndex(index: number): void {
@@ -192,13 +199,27 @@ export class DeckConfigState {
     }
 
     private onCurrentConfigChanged(config: ConfigInner): void {
-        if (!isEqual(config, this.configs[this.selectedIdx].config.config)) {
-            this.configs[this.selectedIdx].config.config = config;
-            this.configs[this.selectedIdx].config.mtimeSecs = 0;
+        const configOuter = this.configs[this.selectedIdx].config;
+        if (!isEqual(config, configOuter.config)) {
+            configOuter.config = config;
+            if (configOuter.id) {
+                this.modifiedConfigs.add(configOuter.id);
+            }
         }
         this.parentLimitsSetter?.(this.getParentLimits());
     }
 
+    private onCurrentAuxDataChanged(data: Record<string, unknown>): void {
+        const current = this.getCurrentAuxData();
+        if (!isEqual(current, data)) {
+            this.currentConfig.update((config) => {
+                const asBytes = new TextEncoder().encode(JSON.stringify(data));
+                config.other = asBytes;
+                return config;
+            });
+        }
+    }
+
     private ensureNewNameUnique(name: string): string {
         const idx = this.configs.findIndex((e) => e.config.name === name);
         if (idx !== -1) {
@@ -210,6 +231,7 @@ export class DeckConfigState {
 
     private updateCurrentConfig(): void {
         this.currentConfig.set(this.getCurrentConfig());
+        this.currentAuxData.set(this.getCurrentAuxData());
         this.parentLimitsSetter?.(this.getParentLimits());
     }
 
@@ -222,6 +244,12 @@ export class DeckConfigState {
         return cloneDeep(this.configs[this.selectedIdx].config.config as ConfigInner);
     }
 
+    /// Extra data associated with current config (for add-ons)
+    private getCurrentAuxData(): Record<string, unknown> {
+        const conf = this.configs[this.selectedIdx].config.config as ConfigInner;
+        return bytesToObject(conf.other);
+    }
+
     private getConfigList(): ConfigListEntry[] {
         const list: ConfigListEntry[] = this.configs.map((c, idx) => {
             const useCount = c.useCount + (idx === this.selectedIdx ? 1 : 0);
@@ -258,3 +286,24 @@ export class DeckConfigState {
         };
     }
 }
+
+function bytesToObject(bytes: Uint8Array): Record<string, unknown> {
+    if (!bytes.length) {
+        return {} as Record<string, unknown>;
+    }
+
+    let obj: Record<string, unknown>;
+    try {
+        obj = JSON.parse(new TextDecoder().decode(bytes)) as Record<string, unknown>;
+    } catch (err) {
+        console.log(`invalid json in deck config`);
+        return {} as Record<string, unknown>;
+    }
+
+    if (obj.constructor !== Object) {
+        console.log(`invalid object in deck config`);
+        return {} as Record<string, unknown>;
+    }
+
+    return obj;
+}