diff --git a/.gitlab/issue_templates/Rebase Browser - Alpha.md b/.gitlab/issue_templates/Rebase Browser - Alpha.md
new file mode 100644
index 0000000000000..f6a09cf5afebc
--- /dev/null
+++ b/.gitlab/issue_templates/Rebase Browser - Alpha.md
@@ -0,0 +1,83 @@
+**NOTE:** All examples in this template reference the rebase from 102.7.0esr to 102.8.0esr
+
+
+ Explanation of Variables
+
+- `$(ESR_VERSION)`: the Mozilla defined ESR version, used in various places for building mullvad-browser tags, labels, etc
+ - **Example**: `102.8.0`
+- `$(ESR_TAG)`: the Mozilla defined hg (Mercurial) tag associated with `$(ESR_VERSION)`
+ - **Example**: `FIREFOX_102_8_0esr_RELEASE`
+- `$(BROWSER_MAJOR)`: the browser major version
+ - **Example**: `12`
+- `$(BROWSER_MINOR)`: the browser minor version
+ - **Example**: either `0` or `5`; Alpha's is always `(Stable + 5) % 10`
+- `$(BASE_BROWSER_BRANCH)`: the full name of the current `base-browser` branch
+ - **Example**: `base-browser-102.8.0esr-12.5-1`
+- `$(BASE_BROWSER_BRANCH_PREV)`: the full name of the previous `base-browser` branch
+ - **Example**: `base-browser-102.7.0esr-12.5-1`
+- `$(BASE_BROWSER_BRANCH_TAG)`: the `base-browser` build tag used as base commit for `mullvad-browser`
+ - **Example**: `base-browser-102.8.0esr-12.5-1-build1`
+- `$(BASE_BROWSER_BRANCH_PREV_TAG)`: the `base-browser` build tag used as base commit for the previous `mullvad-browser`
+ - **Example**: `base-browser-102.7.0esr-12.5-1-build1`
+- `$(MULLVAD_BROWSER_BRANCH)`: the full name of the current `mullvad-browser` branch
+ - **Example**: `mullvad-browser-102.8.0esr-12.5-1`
+- `$(MULLVAD_BROWSER_BRANCH_PREV)`: the full name of the previous `mullvad-browser` branch
+ - **Example**: `mullvad-browser-102.7.0esr-12.5-1`
+
+
+**NOTE:** It is assumed that we've already rebased and tagged `base-browser` alpha and that we've already rebased `mullvad-browser` stable
+
+### **Bookkeeping**
+
+- [ ] Link this issue to the appropriate [Release Prep](https://gitlab.torproject.org/tpo/applications/tor-browser-build/-/issues/?sort=updated_desc&state=opened&label_name%5B%5D=Release%20Prep) issue.
+
+### Update Branch Protection Rules
+
+- [ ] In [Repository Settings](https://gitlab.torproject.org/tpo/applications/mullvad-browser/-/settings/repository):
+ - [ ] Remove previous alpha `mullvad-browser` branch protection rules (this will prevent pushing new changes to the branches being rebased)
+ - [ ] Create new `mullvad-browser` branch protection rule:
+ - **Branch**: `mullvad-browser-$(ESR_VERSION)esr-$(BROWSER_MAJOR).$(BROWSER_MINOR)-1*`
+ - **Example**: `mullvad-browser-102.8.0esr-12.5-1*`
+ - **Allowed to merge**: `Maintainers`
+ - **Allowed to push and merge**: `Maintainers`
+ - **Allowed to force push**: `false`
+
+### **Create and Push New Branch**
+
+- [ ] Create new alpha `mullvad-browser` branch from this ESR's alpha `base-browser` tag
+ - Branch name in the form: `mullvad-browser-$(ESR_VERSION)esr-$(BROWSER_MAJOR).$(BROWSER_MINOR)-1`
+ - **Example**: `git branch mullvad-browser-102.8.0esr-12.5-1 base-browser-102.8.0esr-12.5-1-build1`
+- [ ] Push new `mullvad-browser` branch to `upstream`
+- [ ] Push `base-browser` tag to `upstream`
+
+### **Rebase tor-browser**
+
+- [ ] Checkout a new local branch for the `mullvad-browser` rebase
+ - **Example**: `git branch mullvad-browser-rebase upstream/mullvad-browser-102.8.0esr-12.5-1`
+- [ ] `mullvad-browser` rebase
+ - [ ] Cherry-pick the previous `mullvad-browser` branch's commit range up to the last `mullvad-browser` `build1` tag
+ - **Example**: `git cherry-pick base-browser-102.7.0esr-12.5-1-build1..mullvad-browser-102.7.0esr-12.5-1-build1`
+ - [ ] Rebase and autosquash these newly cherry-picked commits
+ - **Example**: `git rebase --autosquash --interactive upstream/mullvad-browser-102.8.0esr-12.5-1`
+ - [ ] Cherry-pick remainder of patches after the last `mullvad-browser` `buildN` tag
+ - **Example**: `git cherry-pick mullvad-browser-102.7.0esr-12.5-1-build1..upstream/mulvad-browser-102.7.0esr-12.5-1`
+ - [ ] Rebase and autosquash again, this time replacing all `fixup` and `squash` commands with `pick`. The goal here is to have all of the `fixup` and `squash` commits beside the commit which they modify, but kept un-squashed for easy debugging/bisecting.
+ - **Example**: `git rebase --autosquash --interactive upstream/mullvad-browser-102.8.0esr-12.5-1`
+- [ ] Compare patch sets to ensure nothing *weird* happened during conflict resolution:
+ - [ ] diff of diffs:
+ - Do the diff between `current_patchset.diff` and `rebased_patchset.diff` with your preferred difftool and look at differences on lines that starts with + or -
+ - `git diff $(BASE_BROWSER_BRANCH_PREV_TAG)..$(MULLVAD_BROWSER_BRANCH_PREV) > current_patchset.diff`
+ - `git diff $(BASE_BROWSER_BRANCH_TAG)..HEAD > rebased_patchset.diff`
+ - diff `current_patchset.diff` and `rebased_patchset.diff`
+ - If everything went correctly, the only lines which should differ should be the lines starting with `index abc123...def456` (unless the previous `base-browser` branch includes changes not included in the previous `mullvad-browser` branch)
+ - [ ] rangediff: `git range-diff $(BASE_BROWSER_BRANCH_PREV_TAG)..$(MULLVAD_BROWSER_BRANCH_PREV) $(BASE_BROWSER_BRANCH_TAG)..HEAD`
+ - **Example**: `git range-diff base-browser-102.7.0esr-12.5-1-build1..upstream/mullvad-browser-102.7.0esr-12.5-1 base-browser-102.8.0esr-12.5-1-build1..HEAD`
+- [ ] Open MR for the `mullvad-browser` rebase
+- [ ] Merge
+
+### **Sign and Tag**
+
+- [ ] Sign/Tag `HEAD` of the merged `mullvad-browser` branch:
+ - **Tag**: `mullvad-browser-$(ESR_VERSION)esr-$(BROWSER_MAJOR).$(BROWSER_MINOR)-1-build1`
+ - **Message**: `Tagging build1 for $(ESR_VERSION)esr-based stable`
+ - [ ] Push tag to `upstream`
diff --git a/.gitlab/issue_templates/Rebase Browser - Stable.md b/.gitlab/issue_templates/Rebase Browser - Stable.md
new file mode 100644
index 0000000000000..63ba5945af4c7
--- /dev/null
+++ b/.gitlab/issue_templates/Rebase Browser - Stable.md
@@ -0,0 +1,84 @@
+**NOTE:** All examples in this template reference the rebase from 102.7.0esr to 102.8.0esr
+
+
+ Explanation of Variables
+
+- `$(ESR_VERSION)`: the Mozilla defined ESR version, used in various places for building mullvad-browser tags, labels, etc
+ - **Example**: `102.8.0`
+- `$(ESR_TAG)`: the Mozilla defined hg (Mercurial) tag associated with `$(ESR_VERSION)`
+ - **Example**: `FIREFOX_102_8_0esr_RELEASE`
+- `$(BROWSER_MAJOR)`: the browser major version
+ - **Example**: `12`
+- `$(BROWSER_MINOR)`: the browser minor version
+ - **Example**: either `0` or `5`; Alpha's is always `(Stable + 5) % 10`
+- `$(BASE_BROWSER_BRANCH)`: the full name of the current `base-browser` branch
+ - **Example**: `base-browser-102.8.0esr-12.0-1`
+- `$(BASE_BROWSER_BRANCH_PREV)`: the full name of the previous `base-browser` branch
+ - **Example**: `base-browser-102.7.0esr-12.0-1`
+- `$(BASE_BROWSER_BRANCH_TAG)`: the `base-browser` build tag used as base commit for `mullvad-browser`
+ - **Example**: `base-browser-102.8.0esr-12.0-1-build1`
+- `$(BASE_BROWSER_BRANCH_PREV_TAG)`: the `base-browser` build tag used as base commit for the previous `mullvad-browser`
+ - **Example**: `base-browser-102.7.0esr-12.0-1-build1`
+- `$(MULLVAD_BROWSER_BRANCH)`: the full name of the current `mullvad-browser` branch
+ - **Example**: `mullvad-browser-102.8.0esr-12.0-1`
+- `$(MULLVAD_BROWSER_BRANCH_PREV)`: the full name of the previous `mullvad-browser` branch
+ - **Example**: `mullvad-browser-102.7.0esr-12.0-1`
+
+
+**NOTE:** It is assumed that we've already rebased and tagged `base-browser` stable
+
+### **Bookkeeping**
+
+- [ ] Link this issue to the appropriate [Release Prep](https://gitlab.torproject.org/tpo/applications/tor-browser-build/-/issues/?sort=updated_desc&state=opened&label_name%5B%5D=Release%20Prep) issue.
+
+### Update Branch Protection Rules
+
+- [ ] In [Repository Settings](https://gitlab.torproject.org/tpo/applications/mullvad-browser/-/settings/repository):
+ - [ ] Remove previous stable `mullvad-browser` branch protection rules (this will prevent pushing new changes to the branches being rebased)
+ - [ ] Create new `mullvad-browser` branch protection rule:
+ - **Branch**: `mullvad-browser-$(ESR_VERSION)esr-$(BROWSER_MAJOR).$(BROWSER_MINOR)-1*`
+ - **Example**: `mullvad-browser-102.8.0esr-12.0-1*`
+ - **Allowed to merge**: `Maintainers`
+ - **Allowed to push and merge**: `Maintainers`
+ - **Allowed to force push**: `false`
+
+### **Create and Push New Branch**
+
+- [ ] Create new stable `mullvad-browser` branch from this ESR's stable `base-browser` tag
+ - Branch name in the form: `mullvad-browser-$(ESR_VERSION)esr-$(BROWSER_MAJOR).$(BROWSER_MINOR)-1`
+ - **Example**: `git branch mullvad-browser-102.8.0esr-12.0-1 base-browser-102.8.0esr-12.0-1-build1`
+- [ ] Push new `mullvad-browser` branch to `upstream`
+- [ ] Push `base-browser` tag to `upstream`
+- [ ] Push `$(ESR_TAG)` to `upstream`
+
+### **Rebase mullvad-browser**
+
+- [ ] Checkout a new local branch for the `mullvad-browser` rebase
+ - **Example**: `git branch mullvad-browser-rebase upstream/mullvad-browser-102.8.0esr-12.0-1`
+- [ ] `mullvad-browser` rebase
+ - [ ] Cherry-pick the previous `mullvad-browser` branch's commit range up to the last `mullvad-browser` `build1` tag
+ - **Example**: `git cherry-pick base-browser-102.7.0esr-12.0-1-build1..mullvad-browser-102.7.0esr-12.0-1-build1`
+ - [ ] Rebase and autosquash these newly cherry-picked commits
+ - **Example**: `git rebase --autosquash --interactive upstream/mullvad-browser-102.8.0esr-12.0-1`
+ - [ ] Cherry-pick remainder of patches after the last `mullvad-browser` `buildN` tag
+ - **Example**: `git cherry-pick mullvad-browser-102.7.0esr-12.0-1-build1..upstream/mullvad-browser-102.7.0esr-12.0-1`
+ - [ ] Rebase and autosquash again, this time replacing all `fixup` and `squash` commands with `pick`. The goal here is to have all of the `fixup` and `squash` commits beside the commit which they modify, but kept un-squashed for easy debugging/bisecting.
+ - **Example**: `git rebase --autosquash --interactive upstream/mullvad-browser-102.8.0esr-12.0-1`
+- [ ] Compare patch sets to ensure nothing *weird* happened during conflict resolution:
+ - [ ] diff of diffs:
+ - Do the diff between `current_patchset.diff` and `rebased_patchset.diff` with your preferred difftool and look at differences on lines that starts with + or -
+ - `git diff $(BASE_BROWSER_BRANCH_PREV_TAG)..$(MULLVAD_BROWSER_BRANCH_PREV) > current_patchset.diff`
+ - `git diff $(BASE_BROWSER_BRANCH_TAG)..HEAD > rebased_patchset.diff`
+ - diff `current_patchset.diff` and `rebased_patchset.diff`
+ - If everything went correctly, the only lines which should differ should be the lines starting with `index abc123...def456` (unless the previous `base-browser` branch includes changes not included in the previous `mullvad-browser` branch)
+ - [ ] rangediff: `git range-diff $(BASE_BROWSER_BRANCH_PREV_TAG)..$(MULLVAD_BROWSER_BRANCH_PREV) $(BASE_BROWSER_BRANCH_TAG)..HEAD`
+ - **Example**: `git range-diff base-browser-102.7.0esr-12.0-1-build1..upstream/mullvad-browser-102.7.0esr-12.5-1 base-browser-102.8.0esr-12.5-1-build1..HEAD`
+- [ ] Open MR for the `mullvad-browser` rebase
+- [ ] Merge
+
+### **Sign and Tag**
+
+- [ ] Sign/Tag `HEAD` of the merged `mullvad-browser` branch:
+ - **Tag**: `mullvad-browser-$(ESR_VERSION)esr-$(BROWSER_MAJOR).$(BROWSER_MINOR)-1-build1`
+ - **Message**: `Tagging build1 for $(ESR_VERSION)esr-based stable`
+ - [ ] Push tag to `upstream`
diff --git a/.gitlab/merge_request_templates/default.md b/.gitlab/merge_request_templates/default.md
index 067042878302a..11f99c2ea9a79 100644
--- a/.gitlab/merge_request_templates/default.md
+++ b/.gitlab/merge_request_templates/default.md
@@ -3,17 +3,33 @@
### Related Issues
- - mullvad-browser#xxxxx
- - tor-browser-build#xxxxx
+- tor-browser#xxxxx
+- mullvad-browser#xxxxx
+- tor-browser-build#xxxxx
-### Backport Timeline
- - [ ] **Immediate** - patchsets for critical bug fixes or other major blocker (e.g. fixes for a 0-day exploit) OR patchsets with trivial changes which do not need testing (e.g. fixes for typos or fixes easily verified in a local developer build)
- - [ ] **Next Minor Stable Release** - patchset that needs to be verified in nightly before backport
- - [ ] **Eventually** - patchset that needs to be verified in alpha before backport
- - [ ] **No Backport** - patchset for the next major stable
+### Backporting
+
+#### Timeline
+- [ ] **Immediate**: patchset needed as soon as possible
+- [ ] **Next Minor Stable Release**: patchset that needs to be verified in nightly before backport
+- [ ] **Eventually**: patchset that needs to be verified in alpha before backport
+- [ ] **No Backport (preferred)**: patchset for the next major stable
+
+#### (Optional) Justification
+- [ ] **Emergency security update**: patchset fixes CVEs, 0-days, etc
+- [ ] **Censorship event**: patchset enables censorship circumvention
+- [ ] **Critical bug-fix**: patchset fixes a bug in core-functionality
+- [ ] **Consistency**: patchset which would make development easier if it were in both the alpha and release branches; developer tools, build system changes, etc
+- [ ] **Sponsor required**: patchset required for sponsor
+- [ ] **Other**: please explain
+
+### Merging
+- [ ] Merge to `mullvad-browser` - `!fixups` to `tor-browser`-specific commits, new features, security backports
+- [ ] Merge to `base-browser` -`!fixups` to `base-browser`-specific commits, new features to be shared with `mullvad-browser`, and security backports
+ - **NOTE**: if your changeset includes patches to both `base-browser` and `mullvad-browser` please clearly label in the change description which commits should be cherry-picked to `base-browser` after merging
### Issue Tracking
- - [ ] Link resolved issues with appropriate [Release Prep issue](https://gitlab.torproject.org/groups/tpo/applications/-/issues/?sort=updated_desc&state=opened&label_name%5B%5D=Release%20Prep&first_page_size=20) for changelog generation
+- [ ] Link resolved issues with appropriate [Release Prep issue](https://gitlab.torproject.org/groups/tpo/applications/-/issues/?sort=updated_desc&state=opened&label_name%5B%5D=Release%20Prep&first_page_size=20) for changelog generation
## Change Description