error in setting up oauth2-login with google

Setting up Google-Login using 'snap' on Ubuntu 18.04LT: Like described in wiki (https://github.com/wekan/wekan/wiki/OAuth2), I tried to set the snap environment-variables like this:

oauth2-auth-endpoint /o/oauth2/v2/auth oauth2-client-id myclientid.apps.googleusercontent.com oauth2-enabled true oauth2-id-map email oauth2-secret mysecret oauth2-server-url https://accounts.google.com oauth2-token-endpoint https://www.googleapis.com/oauth2/v4/token oauth2-uid-map email oauth2-userinfo-endpoint https://www.googleapis.com/oauth2/v3/tokeninfo oauth2-username-map email ouath2-auth-endpoint /o/oauth2/v2/auth

But if I try to login then with the latest snap version 2.75, I am getting this Java-Script error when I try to login:

8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:183 Uncaught TypeError: a.join is not a function at Object.requestCredential (8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:183) at e.isClient.e.loginWithOidc (8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:185) at Object.click button (8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:155) at 8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:59 at Function.e._withTemplateInstanceFunc (8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:59) at f.View.<anonymous> (8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:59) at 8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:59 at Object.f._withCurrentView (8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:59) at f._DOMRange.<anonymous> (8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:59) at HTMLButtonElement.<anonymous> (8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:59) requestCredential @ 8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:183 e.isClient.e.loginWithOidc @ 8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:185 click button @ 8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:155 (anonymous) @ 8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:59 e._withTemplateInstanceFunc @ 8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:59 (anonymous) @ 8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:59 (anonymous) @ 8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:59 f._withCurrentView @ 8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:59 (anonymous) @ 8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:59 (anonymous) @ 8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:59 dispatch @ 8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:19 g.handle @ 8b9c276396f82f63f4d689cf71a793f2d97dbd30.js?meteor_js_resource=true:19

Are you able to assist me?

Thank you in advance,

benophan