HTTP redirect detection breaks connection in some (corporate) networks

Describe the bug

I want to use one of my NC bookmark app server folders on my company PC. Since a few weeks syncing is not possible any more with the error: Syncing failed with E033: Redirect detected. ( I guess: https://github.com/floccusaddon/floccus/commit/6946fc96c13b108e42af66474d6f1981398416b8)

I’m aware that there is a zscaler proxy which fiddles with the connection. Sync outside of the company network is as expected.

I was not sure whether to label it a bug or feature request. But since it broke a working setup I went with bug.

Expected behavior

For this it would be good to have an option, which is default on, to deactivate this redirect check.

Desktop

• OS: Windows 10
• Browser chrome, firefox, brave
• Floccus version: 4.6.1
• Floccus sync method: nextcloud bookmarks

Server

• OS: [Raspberry Pi OS buster]
• Nextcloud version: [21.0]
• Bookmarks app version: [4.1.0]

Debug log

• Debug log provided

2021-04-08T09:10:50.208Z Starting sync process for account user@domain
2021-04-08T09:10:50.212Z Using "merge default" strategy (no cache available)
2021-04-08T09:10:50.221Z Overriding title of built-in node 1 Bookmarks => Bookmarks Bar
2021-04-08T09:10:50.543Z Syncing failed with E033: Redirect detected. Please install the Bookmarks app on your nextcloud and make sure the nextcloud URL you entered doesn't redirect to a different location.

[efelon]

It’s hard for me to tell how special my case is for your user base. I would be out of options when you choose a).

I don’t know how much effort it would be, but

c) to create a GUI (or even more hidden) option: Allow redirects

By default you would block them.

[efelon]

From Firefox (and Chrome) I get a 307 from the company proxy:

Request:

GET /nc/index.php/apps/bookmarks/public/rest/v2/folder/-1/hash HTTP/1.1 Host: mydomain.eu User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:86.0) Gecko/20100101 Firefox/86.0 Accept: / Accept-Language: en-GB,en;q=0.5 Accept-Encoding: gzip, deflate, br Authorization: Basic **** Connection: keep-alive

Response:

HTTP/1.1 307 Temporary Redirect Content-Length: 0 Access-Control-Allow-Origin: * Location: https://gateway.zscaler.net:443/auD?origurl=https%3A%2F%2Fmydomain.eu%2Fnc%2Findex.php%2Fapps%2Fbookmarks%2Fpublic%2Frest%2Fv2%2Ffolder%2F-1%2Fhash&wexps=1&_ordtok=qk43WVqQF3mkNmPNq2VDq7W0J2 Content-Type: text/html P3P: CP=“NOI ADM DEV PSAi COM NAV OUR OTR STP IND DEM” Set-Cookie: ssm_au_d=1;SameSite=None;Secure;path=/;domain=mydomain.eu