This is part of the Crowdsignal Project editor, rather than WordPress block editor. You will need to be logged into Crowdsignal, and use the Crowdsignal Project editor (https://app.crowdsignal.com/project) in order to access the Upload File Form Block.
The Upload File block is part of the Form blocks group and allows the upload of files in some specific formats.
Adding the Upload File block
To add the Upload block, click the 
button at the top-left side of the screen to open the Block Library. You can now use the search box to find the block using its name or select it from the list of available blocks.
You can also type /upload file on a new line in the editor to quickly add an Upload File block.
Editing the Upload File block
Once you add the Upload block, you’ll see a label placeholder and a button that can be customized to the desired text.
The information box below the button can also be customized with a custom text, or, if untouched, it will dynamically adjust the text to match the allowed file formats.
The Upload block supports the following file formats: pdf, jpg/jpeg/,png, svg and mp4.
You can choose to enable/disable the file formats by accessing the block’s Sidebar on the right side of the screen.
Under the “File Formats” section, click the switches to customize the block to your needs.
Collecting responses
After publishing your project and sharing it with the target audience, visitors will be able to click the select file button and choose the file they want to upload.
In case of wrong file selection, they can click the “Remove” button to remove the selected file or select a new file to replace the previously selected file.
The results
The results report will show the list of uploaded files and allow you to download each file.
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