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Please try SmartGit 21.1 preview with modified low-level-property repositories.maxRepositoriesToOpenByDoubleClick.
Please provide detailed steps how to reproduce the problem on smartgit@syntevo.com. Thanks in advance.
Is this a duplicate of https://smartgit.userecho.com/en/communities/1/topics/672-gerrit-as-hosting-provider ?
Version 21.1 #17066 comes with a primitive image diff (showing both images side by side).
Sorry, I disagree. I think it only would help in simple cases where it is not needed.
"Current line" implies "focused control". Often there is no matching line on the other side, so it only would be helpful in a subset of situations. To see the whole line highlighted, please select the option below the color list:

Already works, as you can see in your screenshot. By default it only highlights the gutter in yellow.
Thanks, this will be implemented in 21.1 preview build 17064. You will have to set the low-level property ignore.supportTrackedDir to true.
SmartGit 21.1 #17063 will have this option in Preferences, Built-in Text Editors, Behavior.
Customer support service by UserEcho
The changelog.txt is only updated for an official preview release, not for each intermediate build. In the preferences, hosting providers section you can find Azure DevOps.