template v-for=item in record template v-for=childrenindex in itemchildren key=childrenvalue tr v-if=childrenvalue ===0 td class=col2 a-checkbox v-modelchecked=

There could be several reasons why the <tr> and <td> elements are not being displayed on the page:

1. Check if the record array and item.children array have data: Make sure that the record array and item.children array have data in them. You can use console.log to check the values of record and item.children.

2. Check if the v-if conditions are being met: Verify if the conditions in the v-if directives are being met. For example, if children.value is always 0, then the <tr> element will only be displayed if the value of children.value is 0. Ensure that the conditions are correct and the elements should be displayed according to those conditions.

3. Check if the checkboxes are being displayed: If the checkboxes are not being displayed, ensure that the a-checkbox component is properly imported and registered in the component where this template is being used.

4. Check the CSS styling: It's possible that the elements are being displayed but are not visible due to CSS styling. Check if there are any CSS rules that may be hiding the elements or causing them to have a height or width of 0.

By checking these possible issues, you should be able to identify the reason why the <tr> and <td> elements are not being displayed on the page