Hi Kirill,
Thanks for posting your concern.
Could you confirm if you are referring to the custom parameters of the landing page? If yes, I am afraid that landing page with the partner code (in this form
purchase_type={bulk}) is currently not possible to retrieve. However, you may utilize the
getCustomParameters() method to get custom parameters of landing page (for sitelinks).
The sample returned value for this method is displayed below.
{key1: 'value1', key2: 'value2', key3: 'value3'}
Moving forward to your concern about setting the custom parameters. You may use the
setCustomParameters(customParameters) for setting the custom parameters for your landing pages (for sitelinks).
Let me know if you have further questions.
Regards,
Ejay
Google Ads Scripts Team

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