vscode-gitlens source code study

[zFitness]

hello, i am studying vscode-gitlens scoure.I want to know what this code does.

item.resourceUri = Uri.from({
				scheme: Schemes.Git,
				authority: 'gitlens-view',
				path: this.uri.path,
				query: JSON.stringify({
					// Ensure we use the fsPath here, otherwise the url won't open properly
					path: this.uri.fsPath,
					ref: this.uri.sha,
					decoration: `gitlens-view://commit-file/status/${this.file.status}`,
				}),
			});

Why can ts's icon and "M" appear? Thanks