Fixed the JavaScript period chooser error when there is no data.

src/accounting/static/js/period-chooser.js

@@ -171,6 +171,7 @@ class MonthTab extends TabPlane {
     constructor(chooser) {
         super(chooser);
         const monthChooser = document.getElementById(this.prefix + "-chooser");
+        if (monthChooser !== null) {
             let start = monthChooser.dataset.start;
             this.#monthChooser = new tempusDominus.TempusDominus(monthChooser, {
                 restrictions: {
@@ -194,6 +195,7 @@ class MonthTab extends TabPlane {
                     .replaceAll("PERIOD", period);
             });
         }
+    }
 
     /**
      * The tab ID
@@ -250,6 +252,7 @@ class DayTab extends TabPlane {
         super(chooser);
         this.#date = document.getElementById(this.prefix + "-date");
         this.#dateError = document.getElementById(this.prefix + "-date-error");
+        if (this.#date !== null) {
             this.#date.onchange = () => {
                 if (this.#validateDate()) {
                     window.location = chooser.modal.dataset.urlTemplate
@@ -257,6 +260,7 @@ class DayTab extends TabPlane {
                 }
             };
         }
+    }
 
     /**
      * Validates the date.
@@ -338,6 +342,7 @@ class CustomTab extends TabPlane {
         this.#end = document.getElementById(this.prefix + "-end");
         this.#endError = document.getElementById(this.prefix + "-end-error");
         this.#conform = document.getElementById(this.prefix + "-confirm");
+        if (this.#start !== null) {
             this.#start.onchange = () => {
                 if (this.#validateStart()) {
                     this.#end.min = this.#start.value;
@@ -358,6 +363,7 @@ class CustomTab extends TabPlane {
                 }
             };
         }
+    }
 
     /**
      * Validates the start of the period.