Merge util not start from GUI

[sternpost]

Hello!

Sourcetree 3.3.8

I carry out the actions:

1. Open the Process Viewer (Tools > Process Viewer...)
2. Run the external diff command
3. We see the command being executed
{
"Command": "git -c diff.mnemonicprefix=false -c core.quotepath=false --no-optional-locks mergetool -y --tool=sourcetree -- CR/fss_cr_revizor/packages/pck_consolidated_report_api.pck",
"Directory": "C:\\Users\\KKorotkov\\Documents\\db-revizor\\DHEIISSS-30123",
"Status": "Finished",
"Duration": "00:00:04.4005065",
"CallerContext": "GetVisualMergeProcess",
"Output": "Merging:\nCR/fss_cr_revizor/packages/pck_consolidated_report_api.pck\n\nNormal merge conflict for 'CR/fss_cr_revizor/packages/pck_consolidated_report_api.pck':\n {local}: modified file\n {remote}: modified file\n"
}

4. Nothing happens.
5. We run it from the command line ('Terminal' button in Sourcetree and paste the command in)
6. The utility opens successfully!!!

What needs to be done so that the merge utility starts from SourceTree?