message: Fix handling of slashed branches in some commits list features
diff: import React from 'dom-chef';
  -import select from 'select-dom';
  import * as pageDetect from 'github-url-detection';
  import features from '.';
  import getDefaultBranch from '../github-helpers/get-default-branch';
  +import {getCurrentCommittish} from '../github-helpers';
  import addAfterBranchSelector from '../helpers/add-after-branch-selector';
  import {getPullRequestsAssociatedWithBranch, stateIcon} from './show-associated-branch-prs-on-fork';
  @@ -15,21 +15,9 @@ const stateColorMap = {
  DRAFT: '',
  };
  -// TODO remove this after #4196 is fixed
  -function getCurrentBranch(): string {
  - const feedLink = select.last('link[type="application/atom+xml"]')!;
  - return new URL(feedLink.href)
  - .pathname
  - .split('/')
  - .slice(4) // Drops the initial /user/repo/route/ part
  - .join('/')
  - .replace(/\.atom$/, '');
  -}
  -
  async function init(): Promise<void | false> {
  - const currentBranch = getCurrentBranch();
  -
  - if (/^[\da-f]{40}$/.test(currentBranch) || await getDefaultBranch() === currentBranch) {
  + const currentBranch = getCurrentCommittish();
  + if (!currentBranch || /^[\da-f]{40}$/.test(currentBranch) || await getDefaultBranch() === currentBranch) {
  return false;
  }
  