5 files changed, 64 insertions, 2 deletions

diff --git a/ext/bg/js/api.js b/ext/bg/js/api.js
index f768e6f9..94a70c34 100644
--- a/ext/bg/js/api.js
+++ b/ext/bg/js/api.js
@@ -241,3 +241,32 @@ function apiFrameInformationGet(sender) {
     const frameId = sender.frameId;
     return Promise.resolve({frameId});
 }
+
+function apiInjectStylesheet(css, sender) {
+    if (!sender.tab) {
+        return Promise.reject(new Error('Invalid tab'));
+    }
+
+    const tabId = sender.tab.id;
+    const frameId = sender.frameId;
+    const details = {
+        code: css,
+        runAt: 'document_start',
+        cssOrigin: 'user',
+        allFrames: false
+    };
+    if (typeof frameId === 'number') {
+        details.frameId = frameId;
+    }
+
+    return new Promise((resolve, reject) => {
+        chrome.tabs.insertCSS(tabId, details, () => {
+            const e = chrome.runtime.lastError;
+            if (e) {
+                reject(new Error(e.message));
+            } else {
+                resolve();
+            }
+        });
+    });
+}
diff --git a/ext/bg/js/backend.js b/ext/bg/js/backend.js
index 453f4282..c1216d95 100644
--- a/ext/bg/js/backend.js
+++ b/ext/bg/js/backend.js
@@ -185,6 +185,7 @@ Backend.messageHandlers = {
     screenshotGet: ({options}, sender) => apiScreenshotGet(options, sender),
     forward: ({action, params}, sender) => apiForward(action, params, sender),
     frameInformationGet: (params, sender) => apiFrameInformationGet(sender),
+    injectStylesheet: ({css}, sender) => apiInjectStylesheet(css, sender)
 };
 
 window.yomichan_backend = new Backend();
diff --git a/ext/bg/js/options.js b/ext/bg/js/options.js
index cadc4443..fac17d68 100644
--- a/ext/bg/js/options.js
+++ b/ext/bg/js/options.js
@@ -278,7 +278,8 @@ function profileOptionsCreateDefaults() {
             mainDictionary: '',
             popupTheme: 'default',
             popupOuterTheme: 'default',
-            customPopupCss: ''
+            customPopupCss: '',
+            customPopupOuterCss: ''
         },
 
         audio: {
diff --git a/ext/bg/js/settings-popup-preview.js b/ext/bg/js/settings-popup-preview.js
index 53a5f1d0..7ccdc7f3 100644
--- a/ext/bg/js/settings-popup-preview.js
+++ b/ext/bg/js/settings-popup-preview.js
@@ -21,6 +21,7 @@ class SettingsPopupPreview {
     constructor() {
         this.frontend = null;
         this.apiOptionsGetOld = apiOptionsGet;
+        this.popupInjectOuterStylesheetOld = Popup.injectOuterStylesheet;
         this.popupShown = false;
         this.themeChangeTimeout = null;
     }
@@ -56,6 +57,9 @@ class SettingsPopupPreview {
 
         await this.frontend.isPrepared();
 
+        // Overwrite popup
+        Popup.injectOuterStylesheet = (...args) => this.popupInjectOuterStylesheet(...args);
+
         // Update search
         this.updateSearch();
     }
@@ -76,6 +80,19 @@ class SettingsPopupPreview {
         return options;
     }
 
+    popupInjectOuterStylesheet(...args) {
+        // This simulates the stylesheet priorities when injecting using the web extension API.
+        const result = this.popupInjectOuterStylesheetOld(...args);
+
+        const outerStylesheet = Popup.outerStylesheet;
+        const node = document.querySelector('#client-css');
+        if (node !== null && outerStylesheet !== null) {
+            node.parentNode.insertBefore(outerStylesheet, node);
+        }
+
+        return result;
+    }
+
     onWindowResize() {
         if (this.frontend === null) { return; }
         const textSource = this.frontend.textSourceLast;
@@ -127,6 +144,11 @@ class SettingsPopupPreview {
         this.frontend.popup.setCustomCss(css);
     }
 
+    setCustomOuterCss(css) {
+        if (this.frontend === null) { return; }
+        this.frontend.popup.setCustomOuterCss(css, true);
+    }
+
     async updateSearch() {
         const exampleText = document.querySelector('#example-text');
         if (exampleText === null) { return; }
@@ -152,7 +174,8 @@ class SettingsPopupPreview {
 
 SettingsPopupPreview.messageHandlers = {
     setText: (self, {text}) => self.setText(text),
-    setCustomCss: (self, {css}) => self.setCustomCss(css)
+    setCustomCss: (self, {css}) => self.setCustomCss(css),
+    setCustomOuterCss: (self, {css}) => self.setCustomOuterCss(css)
 };
 
 SettingsPopupPreview.instance = SettingsPopupPreview.create();
diff --git a/ext/bg/js/settings.js b/ext/bg/js/settings.js
index 900b89bb..77815955 100644
--- a/ext/bg/js/settings.js
+++ b/ext/bg/js/settings.js
@@ -42,6 +42,7 @@ async function formRead(options) {
     options.general.popupTheme = $('#popup-theme').val();
     options.general.popupOuterTheme = $('#popup-outer-theme').val();
     options.general.customPopupCss = $('#custom-popup-css').val();
+    options.general.customPopupOuterCss = $('#custom-popup-outer-css').val();
 
     options.audio.enabled = $('#audio-playback-enabled').prop('checked');
     options.audio.autoPlay = $('#auto-play-audio').prop('checked');
@@ -112,6 +113,7 @@ async function formWrite(options) {
     $('#popup-theme').val(options.general.popupTheme);
     $('#popup-outer-theme').val(options.general.popupOuterTheme);
     $('#custom-popup-css').val(options.general.customPopupCss);
+    $('#custom-popup-outer-css').val(options.general.customPopupOuterCss);
 
     $('#audio-playback-enabled').prop('checked', options.audio.enabled);
     $('#auto-play-audio').prop('checked', options.audio.autoPlay);
@@ -283,6 +285,7 @@ function showAppearancePreview() {
     const settings = $('#settings-popup-preview-settings');
     const text = $('#settings-popup-preview-text');
     const customCss = $('#custom-popup-css');
+    const customOuterCss = $('#custom-popup-outer-css');
 
     const frame = document.createElement('iframe');
     frame.src = '/bg/settings-popup-preview.html';
@@ -300,6 +303,11 @@ function showAppearancePreview() {
         const params = {css: customCss.val()};
         frame.contentWindow.postMessage({action, params}, '*');
     });
+    customOuterCss.on('input', () => {
+        const action = 'setCustomOuterCss';
+        const params = {css: customOuterCss.val()};
+        frame.contentWindow.postMessage({action, params}, '*');
+    });
 
     container.append(frame);
     buttonContainer.remove();