diff --git a/app/assets/javascripts/admin/addon/components/theme-settings-editor.hbs b/app/assets/javascripts/admin/addon/components/theme-settings-editor.hbs
new file mode 100644
index 00000000000..d3884cfdb5f
--- /dev/null
+++ b/app/assets/javascripts/admin/addon/components/theme-settings-editor.hbs
@@ -0,0 +1,23 @@
+<div class="settings-editor">
+  <div>
+    <AceEditor @mode="html" @content={{this.editedContent}} />
+
+    {{#each this.errors as |error|}}
+      <div class="validation-error">
+        {{d-icon "times"}}
+        <b>{{error.setting}}</b>:
+        {{error.errorMessage}}
+      </div>
+    {{/each}}
+  </div>
+
+  <div class="buttons">
+    <DButton
+      @action={{this.save}}
+      id="save"
+      class="btn-primary save"
+      @disabled={{this.saveButtonDisabled}}
+      @translatedLabel={{i18n "admin.customize.theme.save"}}
+    />
+  </div>
+</div>
\ No newline at end of file
diff --git a/app/assets/javascripts/admin/addon/components/theme-settings-editor.js b/app/assets/javascripts/admin/addon/components/theme-settings-editor.js
new file mode 100644
index 00000000000..17993846ace
--- /dev/null
+++ b/app/assets/javascripts/admin/addon/components/theme-settings-editor.js
@@ -0,0 +1,191 @@
+import Component from "@glimmer/component";
+import { action } from "@ember/object";
+import { tracked } from "@glimmer/tracking";
+import { ajax } from "discourse/lib/ajax";
+import { inject as service } from "@ember/service";
+import I18n from "I18n";
+
+export default class ThemeSettingsEditor extends Component {
+  @service dialog;
+
+  @tracked editedContent = JSON.stringify(
+    this.condensedThemeSettings,
+    null,
+    "\t"
+  );
+  @tracked errors = [];
+  @tracked saving = false;
+
+  // we need to store the controller being passed in so that when we
+  // call `save` we have not lost context of the argument
+  customizeThemeShowController = this.args.model?.controller;
+
+  get saveButtonDisabled() {
+    return !this.documentChanged || this.saving;
+  }
+
+  get documentChanged() {
+    try {
+      if (!this.editedContent) {
+        return false;
+      }
+      const editedContentString = JSON.stringify(
+        JSON.parse(this.editedContent)
+      );
+      const themeSettingsString = JSON.stringify(this.condensedThemeSettings);
+      if (editedContentString.localeCompare(themeSettingsString) !== 0) {
+        this.errors = [];
+        return true;
+      } else {
+        return false;
+      }
+    } catch {
+      return true;
+    }
+  }
+
+  get theme() {
+    return this.args.model?.model;
+  }
+
+  get condensedThemeSettings() {
+    if (!this.theme) {
+      return null;
+    }
+    return this.theme.settings.map((setting) => ({
+      setting: setting.setting,
+      value: setting.value,
+    }));
+  }
+
+  // validates the following:
+  // each setting must have a 'setting' and a 'value' key and no other keys
+  validateSettingsKeys(settings) {
+    return settings.reduce((acc, setting) => {
+      if (!acc) {
+        return acc;
+      }
+      if (!("setting" in setting)) {
+        // must have a setting key
+        return false;
+      }
+      if (!("value" in setting)) {
+        // must have a value key
+        return false;
+      }
+      if (Object.keys(setting).length > 2) {
+        // at this point it's verified to have setting and value key - but must have no other keys
+        return false;
+      }
+      return true;
+    }, true);
+  }
+
+  @action
+  async save() {
+    this.saving = true;
+    this.errors = [];
+    this.success = "";
+    if (!this.editedContent) {
+      // no changes.
+      return;
+    }
+    let newSettings = "";
+    try {
+      newSettings = JSON.parse(this.editedContent);
+    } catch (e) {
+      this.errors = [
+        ...this.errors,
+        {
+          setting: I18n.t("admin.customize.syntax_error"),
+          errorMessage: e.message,
+        },
+      ];
+      this.saving = false;
+      return;
+    }
+    if (!this.validateSettingsKeys(newSettings)) {
+      this.errors = [
+        ...this.errors,
+        {
+          setting: I18n.t("admin.customize.syntax_error"),
+          errorMessage: I18n.t("admin.customize.validation_settings_keys"),
+        },
+      ];
+      this.saving = false;
+      return;
+    }
+
+    const originalNames = this.theme
+      ? this.theme.settings.map((setting) => setting.setting)
+      : [];
+    const newNames = newSettings.map((setting) => setting.setting);
+    const deletedNames = originalNames.filter(
+      (originalName) => !newNames.find((newName) => newName === originalName)
+    );
+    const addedNames = newNames.filter(
+      (newName) =>
+        !originalNames.find((originalName) => originalName === newName)
+    );
+    if (deletedNames.length) {
+      this.errors = [
+        ...this.errors,
+        {
+          setting: deletedNames.join(", "),
+          errorMessage: I18n.t("admin.customize.validation_settings_deleted"),
+        },
+      ];
+    }
+    if (addedNames.length) {
+      this.errors = [
+        ...this.errors,
+        {
+          setting: addedNames.join(","),
+          errorMessage: I18n.t("admin.customize.validation_settings_added"),
+        },
+      ];
+    }
+
+    if (this.errors.length) {
+      this.saving = false;
+      return;
+    }
+
+    const changedSettings = newSettings.filter((newSetting) => {
+      const originalSetting = this.theme.settings.find(
+        (_originalSetting) => _originalSetting.setting === newSetting.setting
+      );
+      return originalSetting.value !== newSetting.value;
+    });
+    for (let setting of changedSettings) {
+      try {
+        await this.saveSetting(this.theme.id, setting);
+      } catch (err) {
+        const errorObjects = JSON.parse(err.jqXHR.responseText).errors.map(
+          (error) => ({
+            setting: setting.setting,
+            errorMessage: error,
+          })
+        );
+        this.errors = [...this.errors, ...errorObjects];
+      }
+    }
+    if (this.errors.length === 0) {
+      this.editedContent = null;
+    }
+    this.saving = false;
+    this.dialog.cancel();
+    this.customizeThemeShowController.send("routeRefreshModel");
+  }
+
+  async saveSetting(themeId, setting) {
+    const updateUrl = `/admin/themes/${themeId}/setting`;
+    return await ajax(updateUrl, {
+      type: "PUT",
+      data: {
+        name: setting.setting,
+        value: setting.value,
+      },
+    });
+  }
+}
diff --git a/app/assets/javascripts/admin/addon/controllers/admin-customize-themes-show.js b/app/assets/javascripts/admin/addon/controllers/admin-customize-themes-show.js
index 93f8c56db4b..b37756645c4 100644
--- a/app/assets/javascripts/admin/addon/controllers/admin-customize-themes-show.js
+++ b/app/assets/javascripts/admin/addon/controllers/admin-customize-themes-show.js
@@ -15,6 +15,7 @@ import discourseComputed from "discourse-common/utils/decorators";
 import { makeArray } from "discourse-common/lib/helpers";
 import { popupAjaxError } from "discourse/lib/ajax-error";
 import { url } from "discourse/lib/computed";
+import ThemeSettingsEditor from "admin/components/theme-settings-editor";
 import ThemeUploadAddModal from "../components/theme-upload-add";
 
 const THEME_UPLOAD_VAR = 2;
@@ -251,6 +252,11 @@ export default class AdminCustomizeThemesShowController extends Controller {
     return userId > 0 && !defaultTheme;
   }
 
+  @action
+  refreshModel() {
+    this.send("routeRefreshModel");
+  }
+
   @action
   updateToLatest() {
     this.set("updatingRemote", true);
@@ -396,6 +402,16 @@ export default class AdminCustomizeThemesShowController extends Controller {
     });
   }
 
+  @action
+  showThemeSettingsEditor() {
+    this.dialog.alert({
+      title: "Edit Settings",
+      bodyComponent: ThemeSettingsEditor,
+      bodyComponentModel: { model: this.model, controller: this },
+      class: "theme-settings-editor-dialog",
+    });
+  }
+
   @action
   switchType() {
     const relatives = this.get("model.component")
diff --git a/app/assets/javascripts/admin/addon/routes/admin-customize-themes.js b/app/assets/javascripts/admin/addon/routes/admin-customize-themes.js
index 7f323281ff4..04f1df28105 100644
--- a/app/assets/javascripts/admin/addon/routes/admin-customize-themes.js
+++ b/app/assets/javascripts/admin/addon/routes/admin-customize-themes.js
@@ -18,6 +18,11 @@ export default class AdminCustomizeThemesRoute extends Route {
     return this.store.findAll("theme");
   }
 
+  @action
+  routeRefreshModel() {
+    this.refresh();
+  }
+
   setupController(controller, model) {
     super.setupController(controller, model);
     controller.set("editingTheme", false);
diff --git a/app/assets/javascripts/admin/addon/templates/customize-themes-show.hbs b/app/assets/javascripts/admin/addon/templates/customize-themes-show.hbs
index 8f3682f611f..3de57309c53 100644
--- a/app/assets/javascripts/admin/addon/templates/customize-themes-show.hbs
+++ b/app/assets/javascripts/admin/addon/templates/customize-themes-show.hbs
@@ -496,14 +496,22 @@
           />
         {{/if}}
       {{/if}}
+      {{#if this.hasSettings}}
 
+        <DButton
+          @action={{this.showThemeSettingsEditor}}
+          @label="admin.customize.theme.settings_editor"
+          @icon="pen"
+          @class="btn-default btn-normal"
+          @title="admin.customize.theme.settings_editor"
+        />
+      {{/if}}
       <DButton
         @action={{action "destroyTheme"}}
         @label="admin.customize.delete"
         @icon="trash-alt"
         @class="btn-danger"
       />
-
     </div>
   {{/if}}
 
diff --git a/app/assets/javascripts/discourse/tests/integration/components/admin-theme-settings-editor-test.js b/app/assets/javascripts/discourse/tests/integration/components/admin-theme-settings-editor-test.js
new file mode 100644
index 00000000000..48e42efa7d2
--- /dev/null
+++ b/app/assets/javascripts/discourse/tests/integration/components/admin-theme-settings-editor-test.js
@@ -0,0 +1,141 @@
+import { module, test } from "qunit";
+import { setupRenderingTest } from "discourse/tests/helpers/component-test";
+import { render } from "@ember/test-helpers";
+import { hbs } from "ember-cli-htmlbars";
+/*
+example valid content for ace editor:
+[
+	{
+		"setting": "whitelisted_fruits",
+		"value": "uudu"
+	},
+	{
+		"setting": "favorite_fruit",
+		"value": "orange"
+	},
+	{
+		"setting": "year",
+		"value": 1992
+	},
+	{
+		"setting": "banner_links",
+		"value": "[{\"icon\":\"info-circle\",\"text\":\"about this site\",\"url\":\"/faq\"}, {\"icon\":\"users\",\"text\":\"meet our staff\",\"url\":\"/about\"}, {\"icon\":\"star\",\"text\":\"your preferences\",\"url\":\"/my/preferences\"}]"
+	}
+]
+ */
+
+function glimmerComponent(owner, componentName, args = {}) {
+  const { class: componentClass } = owner.factoryFor(
+    `component:${componentName}`
+  );
+  let componentManager = owner.lookup("component-manager:glimmer");
+  let component = componentManager.createComponent(componentClass, {
+    named: args,
+  });
+  return component;
+}
+
+module(
+  "Integration | Component | admin-theme-settings-editor",
+  function (hooks) {
+    setupRenderingTest(hooks);
+
+    let model;
+
+    test("renders passed json model object into string in the ace editor", async function (assert) {
+      await render(hbs`<ThemeSettingsEditor @model={{hash
+        model=(hash
+         settings=(array
+          (hash
+            setting='setting1'
+            value='value1')
+          (hash
+            setting='setting2'
+            value='value2')
+          )
+        )
+    }} />`);
+      const lines = document.querySelectorAll(".ace_line");
+      assert.strictEqual(lines[0].innerHTML, "[");
+    });
+
+    test("input is valid json", async function (assert) {
+      const component = glimmerComponent(this.owner, "theme-settings-editor", {
+        model: [],
+      });
+      component.editedContent = "foo";
+      component.save();
+      assert.strictEqual(component.errors[0].setting, "Syntax Error");
+    });
+
+    test("'setting' key is present for each setting", async function (assert) {
+      const component = glimmerComponent(this.owner, "theme-settings-editor", {
+        model: [],
+      });
+
+      component.editedContent = JSON.stringify([{ value: "value1" }]);
+      component.save();
+      assert.strictEqual(component.errors[0].setting, "Syntax Error");
+    });
+
+    test("'value' key is present for each setting", async function (assert) {
+      const component = glimmerComponent(this.owner, "theme-settings-editor", {
+        model: [],
+      });
+
+      component.editedContent = JSON.stringify([{ setting: "setting1" }]);
+      component.save();
+      assert.strictEqual(component.errors[0].setting, "Syntax Error");
+    });
+
+    test("only 'setting' and 'value' keys are present, no others", async function (assert) {
+      const component = glimmerComponent(this.owner, "theme-settings-editor", {
+        model: [],
+      });
+
+      component.editedContent = JSON.stringify([{ otherkey: "otherkey1" }]);
+      component.save();
+      assert.strictEqual(component.errors[0].setting, "Syntax Error");
+    });
+
+    test("no settings are deleted", async function (assert) {
+      model = {
+        model: {
+          settings: [
+            { setting: "foo", value: "foo" },
+            { setting: "bar", value: "bar" },
+          ],
+        },
+      };
+      const component = glimmerComponent(this.owner, "theme-settings-editor", {
+        model,
+      });
+
+      component.editedContent = JSON.stringify([
+        { setting: "bar", value: "bar" },
+      ]);
+      component.save();
+
+      assert.strictEqual(component.errors[0].setting, "foo");
+    });
+
+    test("no settings are added", async function (assert) {
+      model = {
+        model: {
+          settings: [{ setting: "bar", value: "bar" }],
+        },
+      };
+
+      const component = glimmerComponent(this.owner, "theme-settings-editor", {
+        model,
+      });
+
+      component.editedContent = JSON.stringify([
+        { setting: "foo", value: "foo" },
+        { setting: "bar", value: "bar" },
+      ]);
+      component.save();
+      assert.strictEqual(component.errors[0].setting, "foo");
+    });
+  }
+);
diff --git a/app/assets/javascripts/discourse/tests/unit/controllers/admin-customize-themes-show-test.js b/app/assets/javascripts/discourse/tests/unit/controllers/admin-customize-themes-show-test.js
index 8de26d68855..9f929804391 100644
--- a/app/assets/javascripts/discourse/tests/unit/controllers/admin-customize-themes-show-test.js
+++ b/app/assets/javascripts/discourse/tests/unit/controllers/admin-customize-themes-show-test.js
@@ -50,4 +50,40 @@ module("Unit | Controller | admin-customize-themes-show", function (hooks) {
       "returns theme's repo URL to branch"
     );
   });
+
+  test("displays settings editor button with settings", function (assert) {
+    const theme = Theme.create({
+      id: 2,
+      default: true,
+      name: "default",
+      settings: [{}],
+    });
+    const controller = this.owner.lookup(
+      "controller:admin-customize-themes-show"
+    );
+    controller.setProperties({ model: theme });
+    assert.deepEqual(
+      controller.hasSettings,
+      true,
+      "sets the hasSettings property to true with settings"
+    );
+  });
+
+  test("hides settings editor button with no settings", function (assert) {
+    const theme = Theme.create({
+      id: 2,
+      default: true,
+      name: "default",
+      settings: [],
+    });
+    const controller = this.owner.lookup(
+      "controller:admin-customize-themes-show"
+    );
+    controller.setProperties({ model: theme });
+    assert.deepEqual(
+      controller.hasSettings,
+      false,
+      "sets the hasSettings property to true with settings"
+    );
+  });
 });
diff --git a/app/assets/stylesheets/common/admin/customize.scss b/app/assets/stylesheets/common/admin/customize.scss
index 925ff47e8cb..39b75d4b0b6 100644
--- a/app/assets/stylesheets/common/admin/customize.scss
+++ b/app/assets/stylesheets/common/admin/customize.scss
@@ -23,6 +23,28 @@
   }
 }
 
+.settings-editor {
+  .ace-wrapper {
+    position: relative;
+    width: 100%;
+    height: 100%;
+    min-height: 300px;
+    .ace_editor {
+      position: absolute;
+      left: 0;
+      right: 0;
+      top: 0;
+      bottom: 0;
+    }
+  }
+}
+
+.theme-settings-editor-dialog {
+  .dialog-footer {
+    display: none;
+  }
+}
+
 .admin-customize.admin-customize-themes {
   .admin-container {
     padding: 0;
diff --git a/config/locales/client.en.yml b/config/locales/client.en.yml
index ef0a16fe7ba..377ac3ff07c 100644
--- a/config/locales/client.en.yml
+++ b/config/locales/client.en.yml
@@ -5063,6 +5063,11 @@ en:
         title: "Customize"
         preview: "preview"
         explain_preview: "See the site with this theme enabled"
+        syntax_error: "Syntax Error"
+        settings_editor: "Settings Editor"
+        validation_settings_keys: "Each item must have only a 'setting' key and a 'value' key."
+        validation_settings_deleted: "These settings were deleted. Please restore them and try again."
+        validation_settings_added: "These settings were added. Please remove them and try again."
         save: "Save"
         new: "New"
         new_style: "New Style"
@@ -5101,6 +5106,7 @@ en:
           create: "Create"
           create_type: "Type"
           create_name: "Name"
+          save: "Save"
           long_title: "Amend colors, CSS and HTML contents of your site"
           edit: "Edit"
           edit_confirm: "This is a remote theme, if you edit CSS/HTML your changes will be erased next time you update the theme."
@@ -5116,6 +5122,7 @@ en:
           extra_files_upload: "Export theme to view these files."
           extra_files_remote: "Export theme or check the git repository to view these files."
           preview: "Preview"
+          settings_editor: "Settings Editor"
           show_advanced: "Show advanced fields"
           hide_advanced: "Hide advanced fields"
           hide_unused_fields: "Hide unused fields"