We have the same issue with the missing expand/collapse and dock icons in Lambda (actually in all themes we have available on 3.7 dev).
testing 3.7 on a dev server in hopes of upgrading from 3.3 next week.
As an admin, I keep the Navigation and Administration blocks docked most of the
time, but at some point I also collapsed the Nav block (the little minus
sign). So, my Nav was collapsed and docked...
we upgraded to 3.7 on dev, my Nav block is there - but no "content" is
displayed, and no way to expand the block (no plus or minus icons). This
only affects the Lambda theme, however, which is what we use on prod.
If I switch themes, Nav works as it should. Switch back to Lambda, empty
(collapsed?) Nav, login as another user (I'm an admin) - Nav works; switch back to me, Nav doesn't work.
Other users currently testing 3.7 on our dev server have not
been affected, and the only difference is that I'm the only one who had a collapsed block prior to the
upgrade (that we've identified thus far).
Here's what my Nav block looks like in 3.7 (Lambda theme):
If I login as another user in the same theme, Nav works (below):
is that, because I had collapsed Nav in Lambda, that information was
transferred to 3.7 during the upgrade. The result is that the new
Lambda, in 3.7, collapses the block rather than expanding it when confronted with obsolete instructions (whereas the other themes expand the block). There seems to be no way to expand the blasted thing in Lambda, now.
Our Moodle host has been working on this for several days to no avail. I've asked them to revert back to 3.3, allow me to expand my Nav block, then upgrade to 3.7 once again to see if my hypothesis is, indeed, correct. We'll see...
Have you had anything similar in terms of issues with Lambda? Any solutions?