Error: "Cannot read property 'concat' of undefined"

[supreetssethi]

Describe what you were doing when the bug occurred:
1.
2.
3.

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Please do not remove the text below this line

DevTools version: 4.7.0-23309eb38

Call stack: at N (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:164715)
at I (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:163849)
at e.getCommitTree (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:166664)
at Ul (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:342328)
at gi (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:32:62450)
at tl (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:32:71793)
at zl (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:32:113765)
at Ic (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:32:104502)
at Tc (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:32:104430)
at Dc (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:32:104298)

Component stack: at Ul (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:342099)
at div
at div
at div
at Co (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:263571)
at chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:366677
at n (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:276314)
at chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:278724
at div
at div
at Xi (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:325177)
at Ge (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:207026)
at sn (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:216342)
at Va (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:293773)
at us (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:371869)

[bvaughn]

Duplicate of #18256

If you have repro instructions, please share them (on that issue)