https://lead-follow-dashboard-wur7ok23.taskade.app/_genesis/vendor/scroll-guard.js

1(function () {
2  if (window.__tskScrollGuard) return;
3  window.__tskScrollGuard = true;
4
5  var NEAR_BOTTOM_PX = 120; // within this of the bottom => reader counts as "at the bottom"
6  var ANCHOR_SLACK_PX = 40; // element within this of content-bottom => it is a bottom anchor
7
8  var stick = new WeakMap(); // scroll container -> boolean "stuck to bottom"
9  var lastTop = new WeakMap(); // scroll container -> last observed scrollTop
10
11  function nearestScrollable(el) {
12    var n = el;
13    while (n && n !== document.body && n !== document.documentElement) {
14      var s = window.getComputedStyle(n);
15      if (/(auto|scroll)/.test(s.overflowY) && n.scrollHeight > n.clientHeight + 1) return n;
16      n = n.parentElement;
17    }
18    return null;
19  }
20
21  function isNearBottom(sc) {
22    return sc.scrollHeight - sc.scrollTop - sc.clientHeight <= NEAR_BOTTOM_PX;
23  }
24
25  // Track sticky state from scroll direction. Capture phase catches scroll on
26  // inner containers (scroll does not bubble). The guard only scrolls down, so
27  // an upward move is the reader escaping; returning near the bottom re-sticks.
28  document.addEventListener(
29    'scroll',
30    function (e) {
31      var sc = e.target;
32      if (!(sc instanceof Element)) return;
33      var prev = lastTop.has(sc) ? lastTop.get(sc) : sc.scrollTop;
34      var now = sc.scrollTop;
35      lastTop.set(sc, now);
36      if (now < prev - 2) stick.set(sc, false);
37      else if (isNearBottom(sc)) stick.set(sc, true);
38    },
39    true,
40  );
41
42  var orig = Element.prototype.scrollIntoView;
43  Element.prototype.scrollIntoView = function () {
44    try {
45      var sc = nearestScrollable(this);
46      if (sc) {
47        var er = this.getBoundingClientRect();
48        var cr = sc.getBoundingClientRect();
49        var elBottomInContent = er.bottom - cr.top + sc.scrollTop;
50        var targetsBottom = sc.scrollHeight - elBottomInContent < ANCHOR_SLACK_PX;
51        if (targetsBottom) {
52          // Default to stuck until the reader proves otherwise by scrolling up.
53          var stuck = stick.has(sc) ? stick.get(sc) : true;
54          if (!stuck) return; // reader scrolled up: keep their place
55          // At the bottom: allow, but instant (no smooth) to kill per-token shake.
56          return orig.call(this, { block: 'end' });
57        }
58      }
59    } catch (e) {
60      /* fall through to native on any measurement error */
61    }
62    return orig.apply(this, arguments);
63  };
64})();