Unable to get the "Modify Permission" option for users under Advance Sharing

When the user goes to "Sharing Status" section under Personal Preferences, the option to "Modify Permissions" is not shown when any shared user is being selected.

Resolution

The account admin can enable the setting by going to Accounts tab-> Account settings-> Security Settings and under these settings, check "Sending" and "Modify existing transactions" for Account Sharing Permissions and hit Save.