Use rich text for buttons

src/timeline/TimelineActions.ts

@@ -170,7 +170,7 @@ export class TimelineActions extends AbstractTimeline {
     const generateTextDate = (type: 'previous' | 'next', event: TimelineEventObject): void => {
       const hasEnd = event?.hasEndDate && event?.displayDate('end')
       if (type === 'previous') {
-        this.#previousEventText.innerText = event?.text ?? ''
+        this.#previousEventText.innerHTML = event?.text ?? ''
         this.#previousEventDate.innerHTML = `<span>${event?.displayDate('start') ?? ''}</span>`
         if (hasEnd) {
           this.#previousEventDate.innerHTML += '<span>↓</span>' + `<span>${event?.displayDate('end')}</span>`
@@ -178,7 +178,7 @@ export class TimelineActions extends AbstractTimeline {
         return
       }
 
-      this.#nextEventText.innerText = event?.text ?? ''
+      this.#nextEventText.innerHTML = event?.text ?? ''
       this.#nextEventDate.innerHTML = `<span>${event?.displayDate('start') ?? ''}</span>`
       if (hasEnd) {
         this.#nextEventDate.innerHTML += '<span>↓</span>' + `<span>${event?.displayDate('end')}</span>`