Import - Column headers in line - Checkbox

I guess you can implement BeforeInsert event, check for data validity there and skip the rows that do not pass the validation.

Put This in Javascript OnLoad Event
$("#headersLineOption1").prop('checked', true);
$("#headersLineOption1").prop('disabled', true);

Thanks @charlesfolder for your reply.

Don't know why, but it disables the checkbox, but it doesn't check it.

Sounds like charlesfolder's code is firing both instructions at the same time and for whatever reasons disabled completes first.
I've noticed that with javascript code before - it doesn't seem to run consecutively.

I would comment out the disabled option firstly to see if the checked code line works and then I would try delaying the disabling instruction with something like.. setTimeout
adjust millieseconds parameter to get as smooth as possible.

Put This in Javascript OnLoad Event
$("#headersLineOption1").prop('checked', true);
setTimeout("$("#headersLineOption1").prop('disabled', true);", 2000);

Make sure you hit the syntax check button my code is air code and I suspect their might be issues with quotations within quotiations.

I asked chatgpt to improve my air code it came up with this.

$("#headersLineOption1").prop('checked', true);
setTimeout(function() {$("#headersLineOption1").prop('disabled', true);}, 2000);

There is no need for disabling the checkbox.

When I put in on load javascript event on the import page only:

$("#headersLineOption1").prop('checked', true);

Nothing happens