Files
feedBack/static/panes/pane-window-host.js
T
topkoa f43779c99e fix(panes): detach the element when the pop-out starts, not when it lands
The window host's place() is asynchronous — it opens the window, waits for
/pane to load, and only then adopts the element in. But the manager emits
`panes:opened` as soon as place() returns, and the chip reacts by putting its
"popped out" stub where the element used to be.

So for that gap the user saw BOTH: the real panel still sitting in its
original spot, and a stub next to it claiming the panel had left. On a window
that never loads, that lasts the full 10s readiness timeout.

Detach the element as soon as we commit to moving it. That is not destructive:
the node keeps its owner document, its listeners and its closures — it is
simply out of the tree, waiting for a document to be adopted into. And if the
window never loads, closePane() puts it straight back at its home, which is
exactly what the failure path already does.

The dock host has no such gap; its place() moves the element synchronously.

Signed-off-by: topkoa <topkoa@gmail.com>
2026-07-12 19:52:32 -04:00

297 lines
15 KiB
JavaScript

/*
* fee[dB]ack — the pop-out window host.
*
* Opens a real OS window and MOVES THE PANE'S ELEMENT INTO IT.
*
* The move is the whole trick, and it works because the pane window is same-origin
* and opener-linked: `document.adoptNode()` re-parents a live node into another
* window's document, and an adopted node keeps its event listeners, its closures,
* and every reference anything else holds to it. So the plugin's panel goes on
* running the plugin's own code in the plugin's own realm — it is just being
* *displayed* somewhere else. It looks and behaves exactly like what was popped
* out, because it is exactly what was popped out.
*
* That is why this file must use `window.open()` and not ask the desktop's main
* process to make a BrowserWindow: a window we didn't open gives us no handle to
* its document, and without the handle there is nothing to adopt into. Electron
* turns this same-origin `window.open()` into a real BrowserWindow anyway (see
* main.ts's setWindowOpenHandler → `action: 'allow'`), and the main process
* recognises it by its frame name and gives it remembered bounds, always-on-top
* and the system tray. We get the OS window AND the DOM link.
*
* Styles come across too — the pane document starts empty, so we copy the app's
* stylesheets into it. Without that the panel would land unstyled, which is the
* one thing a "pop out exactly this" feature cannot do.
*/
(function () {
'use strict';
const panes = window.feedBack && window.feedBack.panes;
if (!panes || typeof panes.registerHost !== 'function') {
console.error('[panes] pane-manager.js must load before pane-window-host.js');
return;
}
// The desktop's main process finds a pane window by this name and attaches
// bounds, tray and always-on-top to it. Keep it in sync with pane-hosts.ts.
const FRAME_PREFIX = 'fbpane-';
const wins = new Map(); // paneId -> Window
let reaper = null;
// A pane window the user closed with the OS X button gets no reliable
// beforeunload (a crashed renderer certainly gets none). Poll `closed` and
// reap — otherwise the pane stays "open" forever, its chip stays stubbed out,
// and the element it holds is stranded in a dead document with no way back.
function _startReaper() {
if (reaper != null) return;
reaper = setInterval(() => {
wins.forEach((w, id) => { if (w.closed) panes.close(id); });
if (!wins.size) { clearInterval(reaper); reaper = null; }
}, 400);
}
// Give the pane document the app's styles, so the panel looks identical.
// Cloned rather than shared: a <link> node can only live in one document, and
// we are not about to steal the app's own stylesheet out of its head.
function _copyStyles(doc) {
// pane.html already links panes.css, so don't clone a second copy of it —
// duplicate sheets cost a redundant fetch and an extra style recalc for no
// change in appearance.
const have = new Set(
Array.from(doc.querySelectorAll('link[rel="stylesheet"]')).map((l) => l.href));
document.querySelectorAll('link[rel="stylesheet"], style').forEach((node) => {
if (node.tagName === 'LINK' && have.has(node.href)) return;
try { doc.head.appendChild(node.cloneNode(true)); } catch (e) { /* skip a node we can't clone */ }
});
// Carry the theme/scale hooks the app hangs on <html> and <body>. v3 keys
// off these for its colour tokens and interface scale, and a panel that
// lands without them renders in the wrong palette at the wrong size.
//
// MERGE, don't assign: pane.html sets `class="fb-pane-window"` on <html>,
// and panes.css hangs the pane window's own chrome off it. Overwriting the
// class list would take that with it and the window would lose its own
// layout — the app's classes and the pane document's are both wanted.
try {
document.documentElement.classList.forEach((c) => doc.documentElement.classList.add(c));
document.body.classList.forEach((c) => doc.body.classList.add(c));
// The inline style on <html> carries the interface-scale custom property
// (--fb-scale). Merge it in rather than replacing the attribute, for the
// same reason.
const scale = document.documentElement.style.cssText;
if (scale) doc.documentElement.style.cssText += ';' + scale;
} catch (e) { /* non-fatal */ }
}
// Wait for the REAL pane document.
//
// window.open() returns immediately, with an `about:blank` document that is
// already readyState 'complete'. Adopt into that and it works for a few
// milliseconds — and then /pane finishes loading, replaces the document, and
// takes the panel with it. The window is left blank and the element is gone.
//
// So we do not trust readyState, and we do not trust 'load' (which may have
// fired for about:blank before we could listen). We wait for the one thing that
// only exists in the document we actually want: pane.html's #fb-pane-root.
function _whenReady(w, onReady, onFail) {
const deadline = performance.now() + 10000;
let reachFailure = null; // why we could never see the pop-out's document
const tick = () => {
if (w.closed) return;
let doc = null;
try { doc = w.document; }
catch (e) {
// A SecurityError here is the one that matters: it means the pop-out
// is not reachable from this realm at all (a separate process /
// browsing-context group), and no amount of waiting will fix it —
// adoptNode can never work.
doc = null;
reachFailure = e;
}
if (doc && doc.readyState !== 'loading') {
// Only ever adopt into the document we actually navigated TO.
// about:blank reports readyState 'complete' from the moment
// window.open() returns, and adopting into it means the panel is
// destroyed when /pane replaces it a moment later.
const href = (doc.location && doc.location.href) || '';
const isPaneDoc = href.indexOf('/pane') >= 0;
if (isPaneDoc) {
// Prefer pane.html's own root, but never fail for want of it —
// a stale cached copy of the page (or a future rename) must not
// leave the user with a blank window and no panel.
const root = doc.getElementById('fb-pane-root') || doc.body;
if (root) { onReady(root); return; }
}
}
if (performance.now() > deadline) {
let why;
if (reachFailure) {
why = 'the pane window\'s document is NOT reachable from this window ('
+ reachFailure.name + ': ' + reachFailure.message
+ ') — it is in a separate process, so the element cannot be moved into it';
} else if (!doc) {
why = 'the pane window exposed no document at all';
} else {
why = 'the pane window never loaded /pane (it is showing '
+ ((doc.location && doc.location.href) || 'an unknown URL')
+ ', readyState ' + doc.readyState + ')';
}
onFail(new Error(why));
return;
}
setTimeout(tick, 25);
};
tick();
}
function _adopt(w, root, spec, el) {
const doc = w.document;
_copyStyles(doc);
// The panel was almost certainly a fixed/absolute overlay pinned to a
// corner of the app. In a window of its own that positioning is nonsense —
// it would sit 72px from the top of a 380px window, still 288px wide, still
// casting a drop shadow over nothing. Neutralise the *placement* while
// touching nothing else about how it looks.
el.classList.add('fb-paned');
root.appendChild(doc.adoptNode(el));
doc.title = spec.title + ' — fee[dB]ack';
// THE ELEMENT MUST LEAVE BEFORE THE DOCUMENT DIES.
//
// When the user closes a pane window, its document is torn down — and the
// panel is inside it. The node itself survives (we hold a reference) and
// comes home looking perfect: right markup, right classes, right size. But
// it comes home DEAD: every event listener in the subtree is gone with the
// document that hosted them. A panel that renders and does nothing.
//
// The `closed` poll cannot save us: by the time `w.closed` is true, the
// document is already gone. `beforeunload` fires while it is still alive, so
// this is the last moment we can get the element out — and panes.close()
// adopts it back into the main document synchronously.
//
// We attach it HERE, not when the window was opened: back then the window
// still held its throwaway about:blank document, and a listener registered
// on that is discarded when /pane replaces it.
w.addEventListener('beforeunload', () => {
if (panes.isOpen(spec.id)) panes.close(spec.id);
});
// Measure LATE. The pane window has not laid out yet at this point (it is
// still being created and shown), so anything read now reports 0x0 whether
// or not there is a real problem.
setTimeout(() => {
if (w.closed || !el.isConnected) return;
const view = doc.defaultView;
const cs = view.getComputedStyle(el);
const rootCs = view.getComputedStyle(root);
console.info('[panes] adopted', spec.id,
'| el:', el.id || el.className,
'| size:', el.offsetWidth + 'x' + el.offsetHeight,
'| display:', cs.display, '| visibility:', cs.visibility, '| opacity:', cs.opacity,
'| position:', cs.position, '| w/h:', cs.width + '/' + cs.height,
'| children:', el.childElementCount,
'| hidden attr:', el.hasAttribute('hidden'),
'| inline style:', el.getAttribute('style') || '(none)',
'| root size:', root.offsetWidth + 'x' + root.offsetHeight, '/', rootCs.display,
'| window inner:', view.innerWidth + 'x' + view.innerHeight,
'| styles:', doc.querySelectorAll('link[rel="stylesheet"], style').length);
}, 400);
}
function place(spec, el) {
const w = window.open(
window.location.origin + '/pane',
FRAME_PREFIX + spec.id,
'popup,width=' + spec.width + ',height=' + spec.height,
);
if (!w) {
// Popup blocked. Throw BEFORE the manager records anything, so the
// caller's panel stays exactly where it is — and say so out loud rather
// than appearing to do nothing.
if (window.fbNotify) {
window.fbNotify.show({
title: 'Pop-out blocked',
message: 'Allow pop-ups for this site to detach ' + spec.title + '.',
icon: '⚠️', accent: '#f59e0b',
});
}
throw new Error('pop-up blocked');
}
wins.set(spec.id, w);
_startReaper();
// Take the element out of the document NOW, not when the window is ready.
//
// Everything below this line is async: the window has to load /pane before
// there is anything to adopt into. But the manager emits `panes:opened` as
// soon as we return, and the chip reacts by putting its "popped out" stub
// where the element used to be — so for that whole gap the user would see
// BOTH the real panel and a stub claiming it had left. On a window that
// never loads, that lasts the full 10s timeout.
//
// Detaching is not destructive: the node keeps its owner document (this
// one), its listeners and its closures. It is simply out of the tree,
// waiting — and if the window never loads, closePane() puts it straight
// back at its home.
el.remove();
_whenReady(w, (root) => {
try { _adopt(w, root, spec, el); }
catch (e) {
console.error('[panes] failed to move', spec.id, 'into its window', e);
panes.close(spec.id); // brings the element home
}
}, (err) => {
console.error('[panes]', spec.id, err);
panes.close(spec.id); // never strand the element in a dead window
});
// The pane window's 'beforeunload' listener is registered in _adopt(), NOT
// here: a listener added now would attach to the window's throwaway
// about:blank document and be discarded when /pane replaces it.
}
function unplace(id, el) {
// Hand the element back unmarked. The manager returns it to its home right
// after this, and it must arrive as the plugin left it — a panel that
// stayed .fb-paned would come back with its own positioning stripped.
if (el) el.classList.remove('fb-paned');
const w = wins.get(id);
wins.delete(id);
// The manager adopts the element back into this document immediately after
// this returns, so the window is empty by the time it closes.
if (w && !w.closed) { try { w.close(); } catch (e) { /* already gone */ } }
}
function focus(id) {
const w = wins.get(id);
if (w && !w.closed) { try { w.focus(); } catch (e) { /* the OS may refuse */ } }
}
// A BROWSER blocks window.open() outside a user gesture, so a pane remembered
// here cannot be restored on page load — it would only ever produce a "blocked"
// toast. Such a pane comes back in the dock, and the chip pops it out again on
// the user's next click. The DESKTOP app has no such restriction, so there a
// pane left popped out comes back popped out, where you left it.
const isDesktop = !!(window.feedBackDesktop && window.feedBackDesktop.panes);
panes.registerHost({
id: 'window',
priority: 10,
autoRestore: isDesktop,
place, unplace, focus,
});
// Our windows; they must not outlive us. A pane window whose opener is gone
// holds an element belonging to a dead document — there is nothing left to
// dock it back into.
window.addEventListener('beforeunload', () => {
wins.forEach((w) => { if (!w.closed) { try { w.close(); } catch (e) { /* ignore */ } } });
});
})();