Is there any way I can re-arrange the custom searches at the sidebar?
Right click the search and choose Edit Search from the menu. Rename the searches alphabetically (or name them 1., 2., 3., etc.).
I did what you say but the searches at the sidebar remained as it is without getting sorted alphabetically.
Open your searches.taskpaper file, and rearrange the search lines in there. Save the searches.taskpaper file and see if that solves the issue.
Easiest way to get to the searches.taskpaper file? Go to the Window menu in TaskPaper, then to StyleSheet, then Open StyleSheet Folder. In the Finder window that just opened, navigate from the Stylesheet folder, to the Configurations folder. You can open searches.taskpaper in TaskPaper and move the search lines around to your desired order.
I hope that helps!
Thank you very much Jim. This worked!