A small script for getting free stuff from the unity asset store

redeem.js

/*
HOW TO USE
##########
- Go to the unity asset store (https://assetstore.unity.com/)
- Select any category and adapt filters to what you want to get
  It is recommended to set the "Hide Purchased Assets" and "Free Assets" to reduce working load.
  You might also set other filters like for example only 3D Characters or 4+ star ratings only
- Open up the developer console (normally F12)
- Copy this script to the Console (you might change the consts at the beginning, numbers are in milliseconds)
- Write "redeemAll();" (without the quotes) in the console and hit enter

DISCLAIMER
##########
The script goes through all the assets it can find and tries to add them to your assets.
It automatically accepts the agreement popup, so you must be aware of the agreements.
Also the script seems to be rather flaky.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS IS” AND ANY EXPRESS OR IMPLIED WARRANTIES, 
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 
THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
const showRedemptions = true;
const showNumberOfRedeemableProductsFoundOnCurrentPage = true;
const showAgreementAccepting = true;
const showMyAssetsOnlyAccepting = true;
const timePerProduct = 5000;
const timeUntilAgreementAcceptance = 1000;
const timeUntilMyAssetsOnly = 2500;
const timeBeforeGoingToNextPage = 10000;

function getAllProductDetails() {
    return document.querySelectorAll('div.uty-prod-details');
}

function getAllRedeemableAssets() {
    return document.querySelectorAll('button[label="Add to My Assets"]');
}

function getAcceptButton() {
    return document.querySelector('button[label="Accept"]');
}

function getAddToMyAssetsOnly() {
    return document.querySelector('button[label="Add to my assets only"]');
}

function getNextButton() {
    return document.querySelector('button[label="Next"]:not(:disabled)');
}

async function redeemCurrentPage(goToNextPage = false) {
    console.log(`[INFO] Searching products on current page`);
    const allProductDetails = Array.from(getAllProductDetails());
    const detailsOfFreeProducts = allProductDetails.filter(product => product.innerHTML.includes('FREE') && product.innerHTML.includes('Add to My Assets'));

    if (showNumberOfRedeemableProductsFoundOnCurrentPage) {
        console.log(`[INFO] Found ${detailsOfFreeProducts.length} products to redeem.`);
    }

    detailsOfFreeProducts.forEach(async (item, index) => {
        setTimeout(function() {
            const firstTextNode = item.querySelector('a div:first-of-type');
            const productName = firstTextNode ? firstTextNode.innerText : 'UNDEFINED';
            const addToMyAssetsButton = item.querySelector('button[label="Add to My Assets"]');
    
            if (showRedemptions) {
                console.log(`[REDEMPTION] ${index+1}/${detailsOfFreeProducts.length} - ${productName}`);
            } 
            addToMyAssetsButton.click();
    
            setTimeout(function() {
                const acceptButton = getAcceptButton();
                if (acceptButton) {
                    if (showAgreementAccepting) {
                        console.log(`[INFO] Accepting agreement for ${productName}`);
                    }
        
                    acceptButton.click();
                }
            }, timeUntilAgreementAcceptance);

            setTimeout(function() {
                const myAssetsOnly = getAddToMyAssetsOnly();
                if (myAssetsOnly) {
                    if (showMyAssetsOnlyAccepting) {
                        console.log(`[INFO] Adding ${productName} to my assets only`);
                    }
        
                    myAssetsOnly.click();
                }
            }, timeUntilMyAssetsOnly);
    

        }, index * timePerProduct);
        
    });

    setTimeout(function() {
        console.log('[INFO] Page should be done by now');
        const nextButton = getNextButton();

        if (goToNextPage && nextButton) {
            console.log('[INFO] Going to next page');
            nextButton.click();

            setTimeout(function() {
                console.log('[INFO] Start redeeming new page');
                redeemCurrentPage(goToNextPage);
            }, timeBeforeGoingToNextPage);
        }
    }, detailsOfFreeProducts.length * timePerProduct + timeBeforeGoingToNextPage);
}

async function redeemAll() {
    redeemCurrentPage(true);
}

Tweaked your code, thanks (this might loop infinitely if it cant find products anymore):

const showRedemptions = true;
const showNumberOfRedeemableProductsFoundOnCurrentPage = true;
const showAgreementAccepting = true;
const showMyAssetsOnlyAccepting = true;
const timePerProduct = 500;
const timeUntilAgreementAcceptance = 1000;
const timeUntilMyAssetsOnly = 2500;
const timeBeforeGoingToNextPage = 10000;

function getAllProductDetails() {
    return document.querySelectorAll("div._3YDeD");
}

function getNextButton() {
    return document.querySelector('button[label="Next"]:not(:disabled)');
}

function getCookie(name) {
    const value = `; ${document.cookie}`;
    const parts = value.split(`; ${name}=`);
    if (parts.length === 2) return parts.pop().split(';').shift();
}

function sleep(ms) {
    return new Promise(resolve => setTimeout(resolve, ms));
}

async function redeemCurrentPage(goToNextPage = false) {
    console.log(`[INFO] Searching products on current page`);
    const allProductDetails = Array.from(getAllProductDetails());
    const detailsOfFreeProducts = allProductDetails.filter(product => product.innerHTML.includes('FREE') && product.innerHTML.includes('Add to My Assets'));

    if (showNumberOfRedeemableProductsFoundOnCurrentPage) {
        console.log(`[INFO] Found ${detailsOfFreeProducts.length} products to redeem.`);
    }

    for (let index = 0; index < detailsOfFreeProducts.length; index++) {
        const item = detailsOfFreeProducts[index]
        const firstTextNode = item.querySelector('div[data-test="package-title"]');
        const href = item.querySelectorAll("a")[1].href.split("-");
        const id = href[href.length - 1];
        const productName = firstTextNode ? firstTextNode.innerText : 'UNDEFINED';

        try {
            const r = await fetch("https://assetstore.unity.com/api/graphql", {
                "headers": {
                    "operations": "AddToDownload",
                    "x-csrf-token": getCookie('_csrf'),
                    "x-requested-with": "XMLHttpRequest",
                    "x-source": "storefront, storefront"
                },
                "body": `{\"query\":\"mutation AddToDownload($id: String!) {\\n  addToDownload(id: $id) {\\n    id\\n    userOverview {\\n      lastDownloadAt: last_downloaded_at\\n      __typename\\n    }\\n    userEntitlement {\\n      id\\n      orderId\\n      grantTime\\n      __typename\\n    }\\n    __typename\\n  }\\n}\\n\",\"variables\":{\"id\":\"${id}\"},\"operationName\":\"AddToDownload\"}`,
                "method": "POST",
            });

            if (showRedemptions && r.ok) {
                console.log(`[REDEEMED] ${index+1}/${detailsOfFreeProducts.length} - ${productName} (${id})`);
            }
        } catch (err) {
            console.error(err);
        }

        await sleep(timePerProduct);
    }

    console.log('[INFO] Page should be done by now');
    const nextButton = getNextButton();

    if (goToNextPage && nextButton) {
        console.log('[INFO] Going to next page');
        nextButton.click();

        while (getAllProductDetails().length <= 0) await sleep(timeBeforeGoingToNextPage);

        console.log('[INFO] Start redeeming new page');
        redeemCurrentPage(goToNextPage);
    }
}

async function redeemAll() {
    redeemCurrentPage(true);
}

the script shows "undefined", how to solve this issue ?