UI: fix behaviour of hotkey "escape" when closing previews and nearby images popups

src/UI/Base/Hotkeys.ts

@@ -14,6 +14,8 @@ export default class Hotkeys {
         }[]
     > = new UIEventSource([])
 
+    private static readonly seenKeys: Set<string> = new Set()
+
     /**
      * Register a hotkey
      * @param key
@@ -51,6 +53,9 @@ export default class Hotkeys {
             }
         }
 
+        const keyString = JSON.stringify(key)
+        this.seenKeys.add(keyString)
+
         this._docs.data.push({ key, documentation, alsoTriggeredBy })
         this._docs.ping()
         if (Utils.runningFromConsole) {

src/UI/Base/Popup.svelte

@@ -56,6 +56,7 @@
         <slot name="header" />
       </h1>
     {/if}
+    <slot name="closebutton" />
   </svelte:fragment>
   <slot />
   {#if $$slots.footer}