Through a series of oversights I installed a fresh Ubuntu 18.04 installation on a machine that had previously had a Ubuntu 16.04 and Windows 7 dual boot. After using the machine, I have now found this out. I managed to de-allocate the windows partitions which resulted in two non-contiguous unallocated spaces on my 250GB drive with the Ubuntu installation and its swap in the middle.
Using a Ubuntu live system, from a bootable USB, I can now interact with the partitions using gparted. I am attempting to resize the Ubuntu partition.
Starting from the left I am attempting to resize the Ubuntu partition with all of the unallocated space. The center shows the alterations, and the right shows an error from gparted.
From how I understand this error, the actions above would result in the start of the boot sector moving on the drive in such a way that the boot loader would not know where the boot sector starts (thus bricking the installation).
What is the proper way to resize the Ubuntu partition so that the ~190GB of unallocated space is now usable?
EDIT: This SO-QA reads to me that this is just a blanket statement and I should be fine, especially that I only have the single installation.