Merge branch 'dev'

diff --cc docs/configuration.md
Simple merge

diff --cc docs/setup.md
Simple merge

diff --cc src-ui/src/environments/environment.prod.ts
index 344bca6a19710ab7acf3ac0b2eb0024195ea1f68,aa7f64c138e2437285b7f5eba6688cea71303347..f2ae0232602b1c909099a6009334e34497513109
--- 1/src-ui/src/environments/environment.prod.ts
--- 2/src-ui/src/environments/environment.prod.ts
+++ b/src-ui/src/environments/environment.prod.ts
@@@ -3,9 -3,9 +3,9 @@@ const base_url = new URL(document.baseU
  export const environment = {
    production: true,
    apiBaseUrl: document.baseURI + 'api/',
-   apiVersion: '3',
+   apiVersion: '4',
    appTitle: 'Paperless-ngx',
 -  version: '2.2.0-dev',
 +  version: '2.2.1',
    webSocketHost: window.location.host,
    webSocketProtocol: window.location.protocol == 'https:' ? 'wss:' : 'ws:',
    webSocketBaseUrl: base_url.pathname + 'ws/',