How to handle a full browser reload

Overview

What's the recommended way of handling the case where a user hits the "reload" button on their browser? When this happens the host param is missing (which is provided by Shopify when someone first navigates to the app) and then the call to createApp (from @shopify/app-bridge fails) with a complaint about host missing.

11:04:50.219 Uncaught (in promise) 
Object { name: "AppBridgeError", message: "APP::ERROR::INVALID_CONFIG: host must be provided", stack: "AppBridgeError@https://ga.jspm.io/npm:@shopify/app-bridge-core@1.0.1/actions/Error/index.js:1:1675\nfromAction@https://ga.jspm.io/npm:@shopify/app-bridge-core@1.0.1/actions/Error/index.js:1:1844\nvalidateAndDecodeConfig@https://ga.jspm.io/npm:@shopify/app-bridge@3.7.4/index.js:5:4112\ncreateClientApp$1/<@https://ga.jspm.io/npm:@shopify/app-bridge@3.7.4/index.js:5:2733\ncreateApp$1@https://ga.jspm.io/npm:@shopify/app-bridge@3.7.4/index.js:12:89\ninitShopifyApp@https://crowdfunder-octolabs.ngrok.io/assets/superliner/shopify_app-4337f031.js:187:16\ninitPage@https://crowdfunder-octolabs.ngrok.io/assets/superliner/shopify_app-4337f031.js:243:9\n@https://crowdfunder-octolabs.ngrok.io/assets/superliner/shopify_app-4337f031.js:258:3\n", action: undefined, type: "APP::ERROR::INVALID_CONFIG" }
shopify_app-4337f031.js:243:9

Possibly related to: https://github.com/Shopify/shopify_app/issues/1768

Possibly moot if a splash page really isn't needed anymore: https://github.com/Shopify/shopify_app/issues/1946

Start by reviewing the createApp call from @shopify/app-bridge and the initShopifyApp and initPage locations shown in the stack trace. Read the related issues 1768 and 1946 for context. Done means establishing and documenting the supported behavior for a full browser reload when the Shopify-provided host parameter is absent.