Work fine on Old 3ds 10.0.0-27E.
Here my step :
- Put off Wifi.
- Load Browser
- Wait for it to show me the error that it doesn't have connectivity.
- Clear Internet Cookie & Hist.
- Put Original Black Theme back.
- Press L+R on home menu.
- Scan the QR Code
- Click ok to launch it on browser.
- Wait for the browser to throw me error about connectivity.
- Switch on Wifi.
- Load Browser
- Add the current page on fav (in case)
- Click on up left corner of the touch screen (the bar)
- Got a Yellow then Grey and then Red touch screen and it loaded my homebrew menu.
Enjoy Carefully follow that step if you have problems on old 3ds it work everytime in these condition for me. enjoy and thank i can get back my OOT back to normal (I quite hate to see my save data ruined

)