A link can set which kinds the timeline shows

timeline/index.html

@@ -987,11 +987,28 @@ <h2 data-de="Wie man es liest">How to read it</h2>
   // began while a role ran still did. The selection is state, not a place: remembered in
   // the browser like the card's width, never written into the address — and a link to a
   // row of a kind that is off turns that kind back on, because a link must land.
+  //
+  // A link can still set it. ?kinds= names the kinds to show, by name and in any case,
+  // comma-separated: those are on and the rest off, and the page reads it the way it reads
+  // ?lang= — once, on arrival, then strips it from the address and remembers the selection
+  // as if the menu had been used, so the link hands the visitor a view and nothing they
+  // copy afterwards carries it. A name the model does not know is dropped, and a list naming
+  // no kind at all is ignored whole rather than emptying the ledger.
   var KINDS = data.entities.filter(function(e){ return e.type === "experience-kind"; })
     .sort(function(a, b){ return a.name.localeCompare(b.name, "en"); });
   var KIND_KEY = "timeline-kinds", on = {};
   KINDS.forEach(function(k){ on[k.name] = true; });
   try { var saved = JSON.parse(localStorage.getItem(KIND_KEY) || "null"); if (saved) KINDS.forEach(function(k){ if (k.name in saved) on[k.name] = !!saved[k.name]; }); } catch (e) {}
+  var linked = /[?&]kinds=([^&#]*)(&|$)/.exec(location.search), linkedKinds = null;
+  if (linked) {
+    var named = decodeURIComponent(linked[1]).toLowerCase().split(",");
+    var known = KINDS.filter(function(k){ return named.indexOf(k.name.toLowerCase()) >= 0; });
+    if (known.length) { linkedKinds = {}; KINDS.forEach(function(k){ linkedKinds[k.name] = known.indexOf(k) >= 0; }); }
+    try {
+      var q = location.search.replace(/([?&])kinds=[^&#]*(&|$)/, "$1").replace(/[?&]$/, "");
+      history.replaceState(null, "", location.pathname + q + location.hash);
+    } catch (e) {}
+  }
   var kinds = document.getElementById("kinds"), kindsLabel = document.getElementById("kindslabel"), kindsMenu = document.getElementById("kindsmenu");
   var none = h("li", null, "none"); none.hidden = true; ol.appendChild(none);
   var boxes = [];
@@ -1087,7 +1104,7 @@ <h2 data-de="Wie man es liest">How to read it</h2>
   window.addEventListener("hashchange", arrive);
   new MutationObserver(render).observe(document.documentElement, { attributes: true, attributeFilter: ["lang"] });
 
-  applyKinds();
+  if (linkedKinds) { on = linkedKinds; applyKinds(true); } else applyKinds();
   arrive();
 }
 

timeline/og.sha

@@ -1 +1 @@
-4e61cc3847555fee53e2bee1397ed745291be6cddfabbc66b882562466fbc59a
+c82190396ef09ea5f16cd25f466022be5b674e4828d9e1e9172acee71c1c1f10

verify/check.mjs

@@ -311,7 +311,27 @@ const CHECKS = {
     await page.goto(BASE + spec.path + "#" + target);
     const opened = await page.evaluate((id) => document.getElementById(id).open, target);
     if (!opened) return `arriving at #${target} did not open that row`;
-    // Leave the page as it was found — at rest, no row open — for whatever check runs next.
+    // Arriving with ?kinds= sets the selection from the address: the kinds named are on and
+    // the rest off, the parameter leaves the address the way ?lang= does, and the selection
+    // is remembered as if the menu had been used. A name the model does not know is ignored,
+    // and a list naming no kind at all is ignored whole.
+    await page.goto(BASE + spec.path + "?kinds=" + kindOff.toLowerCase() + ",nosuchkind");
+    const linked = await page.evaluate((kind) => ({
+      hidden: [...document.querySelectorAll("#ledger li.k-" + kind.toLowerCase())].filter(li => li.hidden).length,
+      others: [...document.querySelectorAll("#ledger li:has(details)")].filter(li => !li.classList.contains("k-" + kind.toLowerCase()) && !li.hidden).length,
+      label: document.getElementById("kindslabel").textContent, search: location.search,
+      stored: (() => { try { return JSON.parse(localStorage.getItem("timeline-kinds")); } catch (e) { return null; } })() }), kindOff);
+    if (linked.hidden) return `?kinds=${kindOff} hid ${linked.hidden} rows of that kind`;
+    if (linked.others) return `?kinds=${kindOff} left ${linked.others} rows of other kinds showing`;
+    if (linked.label !== kindOff) return `with ?kinds=${kindOff} the filter reads ${JSON.stringify(linked.label)}`;
+    if (linked.search) return `the address still carries ${linked.search}`;
+    if (!linked.stored || linked.stored[kindOff] !== true || Object.keys(linked.stored).some(k => k !== kindOff && linked.stored[k])) return `?kinds=${kindOff} was not remembered: ${JSON.stringify(linked.stored)}`;
+    await page.goto(BASE + spec.path + "?kinds=nosuchkind");
+    const ignored = await page.evaluate(() => ({ hidden: [...document.querySelectorAll("#ledger li:has(details)")].filter(li => li.hidden).length, label: document.getElementById("kindslabel").textContent }));
+    if (ignored.label !== kindOff) return `?kinds naming no kind changed the selection to ${JSON.stringify(ignored.label)}`;
+    // Leave the page as it was found — at rest, every kind on, no row open — for whatever
+    // check runs next.
+    await page.evaluate(() => { try { localStorage.removeItem("timeline-kinds"); } catch (e) {} });
     await page.goto(BASE + spec.path);
     return null;
   },