Issue with custom fieldtype trying to use CP/FilePicker in grid field

Hi,

I’m trying to port an EE2 plugin I created to EE3.

I’ve got the vanilla fieldtype working fine but I’m having an issue when trying to get it to work in a grid field.

In my display_field method I have the following code:

$file_picker_link = ee('CP/FilePicker')->make()
     ->setDirectories($allowed_directory)
     ->getLink(lang('wscropper:select_file'))
     ->setAttribute('class', 'btn action ws-cropper-load-filepicker')
     ->asThumbs()
     ->enableFilters()
     ->enableUploads()
     ->render();

...


$fdata['file_picker_link'] = $file_picker_link;
return ee('View')->make('wscropper:ft_display')->render($fdata);

and in my view I have:

<?php echo $file_picker_link; ?>

When I click the file upload link I just get a blank modal.

If I have a vanilla version of my field in the field group and click the link then the modal works fine and then I can click on my grid field version of the link and it works. Gif of that here: