Ongoing problems connecting a Canon CanoScan 4400F scanner to Linux Mint

This post is about the experiences I've had connecting a Canon CanoScan 4400F scanner to various computers, primarily focusing on my current laptop which, as of the time of first writing this post, ran Linux Mint 19 "Tara" MATE along with Microsoft Windows 10. For context, I am hoping to scan some of my personal & work notebooks for personal archival. I figured that this scanner, which I've had for a long time, does a good job at rendering images, even though it is quite old & slow, so I should continue using it for as long as it continues to work.

I used to use this scanner regularly with my previous laptop, which is an ASUS U30Jc and, when I last ran it regularly, ran Linux Mint 18.3 "Sylvia" along with Microsoft Windows 7; initially when I connected the scanner to the old laptop (a few years ago), it didn't work with Linux Mint out-of-the-box, so I decided to do all scans in Microsoft Windows and then transfer files between partitions later. I stopped using that laptop approximately 2 years ago, and since then until the beginning of this month, it just sat in a box gathering dust. At the beginning of this month, desirous of using this scanner again for the aforementioned purposes, I brought out the old laptop & scanner, but found out that in the intervening 2 years, the damage to the laptop's screen & hinge had worsened, the battery had completely died due to no charging in that time, and the laptop (on either OS) would randomly overheat & shut off. At this point, I now believe that old laptop should be junked.

My current laptop is an ASUS ZenBook UX331UN. I didn't think the scanner would work with it, because it uses USB 1.1, and I remember having trouble getting this laptop to read an older USB device. Just for the heck of it, I decided to connect the scanner to see what happens. Just as with my old laptop, in Linux Mint, the Simple Scan application didn't find any connected scanners. However, I had the idea to run the command "sudo simple-scan" from the terminal. That showed that the scanner was in fact being recognized, so this was probably a permission problem; I also realized that the earlier problem with another old USB device was specific to that device and not a general issue with this laptop reading any older USB device. That said, when I tried to scan a document, I got a window showing the error "Failed to scan: Unable to connect to scanner". Follow the jump to see more.

Airport Traveling Gripes

In a week and a half, I will be heading back home by airplane for the Thanksgiving holidays. Thus, I will have to deal with all the truly ridiculous "security" measures at the airport that are being talked about today.
(Side note: there's a really nice xkcd comic about this as well, discussing how inconsistent it is to confiscate small liquid containers yet allow laptop batteries to go through.)
Anyway, there seems to be a real backlash (Derek Kravitz, Washington Post) against the new super-restrictive rules regarding full-body frisks and scanners; while before, when new restrictions were put in place, people would grudgingly accept them and move on, now most people think these particular rules cross the line of decent and sane security measures into the realm of indecency and violation of rights.
There are a couple of things I don't get about this (the new frisking measures, not the backlash). It seems like this was prompted by a plot to blow up a cargo plane. Does anyone else see anything wrong with this? OK, I'll say it: why should a plot to sneak explosives onto a cargo plane and detonate them remotely lead to restrictions allowing security officials to pat you down fully on passenger planes? There seems to be no cause-effect connection at all here; it just seems totally arbitrary.
Furthermore, the numerous quotes of passengers describing these new rules as the TSA treating passengers like criminals isn't hyperbole by any means; an analyst at a security consultancy in Oregon has described the new procedures as "the same frisking that police use with probable cause". This is more serious than "reasonable suspicion"; this means that the TSA has a strong feeling that every single traveler is probably a terrorist. Hence, I will also say this to the TSA: stop treating us like criminals! What ever happened to the presumption of innocence?
Finally, why is it OK for the government to be violating people like this? I remember learning in a set of videos required by my college over the summer that "unless there's consent, it's assault". Does that mean they're technically sexually assaulting us all? Or are they going to pull the excuse of "by flying, you are automatically consenting to all of our procedures"?