they made a small patch and the current way described in the walktrough doesnt work anymore.
how i managed to do it is go to the same file go to line 196
switch (pageWithContext.page) {
and make a breakpoint there.
just click on a page in the menu to your left in my example i clicked on stats.
then when the breakpoint is activated.
look at pages click
pages: Array(3)it opens a little list
then click
0: {page: 'Stats'} it drops it down
and you will see
page: "Stats" i simply changed it to
Dev and clicked resume to get to the dev page from there i enabled all achievements.