```mermaid %%{init: { 'logLevel': 'debug', 'theme': 'base', 'gitGraph': {'showBranches': true, 'showCommitLabel':true,'mainBranchName': 'HISTORY'}} }%% gitGraph commit id:"2013" commit id:"2015" tag:"R&D" commit id:"2018" tag:"R&D" type: HIGHLIGHT branch v1 checkout v1 commit id:"2020" tag:"release" checkout HISTORY merge v1 branch v2 checkout v2 commit id:"2021" tag:"release" checkout HISTORY merge v2 commit id:"🔥" ```