How did I upgrade tradefurniturecompany.co.uk from Magento 2.3.2 to 2.3.6-p1?

Step 1

bin/magento maintenance:enable

Step 2

I replaced the the root’s composer.json file with the file from Magento 2.3.6-p1.
Then I declared already installed third-party packages in the require section of the file:

Step 3

composer require mailchimp/mc-magento2:102.3.*

It fixes the error

Step 4

rm -rf composer.lock
composer update

Step 5

Then I restored patches in Magento files (which have been overwritten by composer update).

5.1. lib/web/fotorama/fotorama.js

5.2. pub/errors/default/503.phtml

5.3. vendor/magento/framework/Stdlib/Cookie/PhpCookieManager.php

5.4. vendor/magento/framework/View/Element/Template/File/Validator.php

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5.5. vendor/magento/module-paypal/Model/Api/Nvp.php

5.6. vendor/magento/module-quote/Model/ChangeQuoteControl.php

Step 6

It fixes the error:

Step 7

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Step 8

Step 9

Step 10

Step 11

bin/magento setup:upgrade
bin/magento cache:enable

Step 12

I disabled the preinstalled Magento’s crapware:

bin/magento module:disable Dotdigitalgroup_Chat
bin/magento module:disable Magento_NewRelicReporting
bin/magento module:disable Magento_Signifyd
bin/magento module:disable Vertex_AddressValidation
bin/magento module:disable Yotpo_Yotpo

Step 13

rm -rf var/di var/generation generated/*
bin/magento setup:di:compile
bin/magento cache:clean
rm -rf pub/static/* var/cache var/page_cache var/view_preprocessed
bin/magento setup:static-content:deploy \
	--area adminhtml \
	--theme Magento/backend \
	-f en_US en_GB
bin/magento setup:static-content:deploy \
	--area frontend \
	--theme TradeFurnitureCompany/default \
	-f en_GB
bin/magento cache:clean
bin/magento maintenance:disable

How did I upgrade tradefurniturecompany.co.uk from Magento 2.3.6-p1 to 2.3.7-p4?