This especially matters when building using tagged APT snapshots.
I've just seen a 3.0~beta2 build fail with:

  Package 'linux-headers-686-pae' is not installed, so not removed
  Package 'linux-headers-amd64' is not installed, so not removed
  Package 'linux-headers-generic' is not installed, so not removed
  Package 'linux-headers' is not installed, so not removed
  E: Unable to locate package ^linux-source-*
  E: Couldn't find any package by glob '^linux-source-*'
  E: Couldn't find any package by regex '^linux-source-*'
  E: Unable to locate package dpatch
  E: Unable to locate package gcc-4.8
  E: Couldn't find any package by glob 'gcc-4.8'
  E: Couldn't find any package by regex 'gcc-4.8'
  E: Unable to locate package gcc-4.9
  E: Couldn't find any package by glob 'gcc-4.9'
  E: Couldn't find any package by regex 'gcc-4.9'
  E: Unable to locate package gcc-5
  E: Unable to locate package gcc-5-base
  E: Unable to locate package libgl1-mesa-dev

Due to #12308 they break the build of releases based on feature/stretch (3.0~*).
These sources are useless currently as Stretch as the same version
of obfs4proxy.

I'll file a ticket immediately about reverting this commit once that repository
has packages more recent than Stretch's ones.

Due to #12308 they currently break the build of releases based on
feature/stretch (3.0~*). These sources are useless currently as Stretch has no
security support yet.

I'll file a ticket immediately about reverting this commit once debian-security
has packages for Stretch.

Sometimes Dogtail will find the button and click it before it is
shown (searchShowingOnly is not perfect) which generally means
clicking somewhere on the Terminal => the click is lost *and* the
installer does no go to the foreground. So let's wait a bit extra.

This is vs #12059, which changes the semantics of Dogtail so that
nodes are searched for on Dogtail::* object creation.

Refs: #12059

Normally we always start the browser via the 'I start the Tor Browser'
step, which sets @torbrowser, but this step does it too, so let's set
it there as well.

This reverts commit 75449088.

I need the test suite working to release 3.0~beta2, and it's been quite broken
on feature/stretch since the merge of test/12059-dogtail-optimizations.

refs: #12305

Details: <CAJdkzENJZUET8wQoisevWK3p-AVAbaCMm7==J4hUAFrBC62U-A@mail.gmail.com>

Merge branch 'web/tails-2.11-release-notes' of https://git-tails.immerda.ch/tails into web/tails-2.11-release-notes