With all info given, it is indeed weird.
I have 1 possible idea, very unlikely:
Did you had addons, and you did NOT bundle them in your project, so each test you did on other computers and browsers, you had to install those addons, then open your project and get errors?
If that is what you're doing, then, did you modify those addons or update them?
I say all of this, because, I tinkered with addons before and this made projects unable to be opened (didn't check console when this happened).
Beyond this, I may be wrong, but, might be worth emailing your project to Scirra's support email, as, it's not a bug, but it's a severe issue with your project. Just clarify in the email what you've tried, other computers, other browsers, older C3, older backups, etc.
It may be impossible for them to solve, or may be a huge endeavour for Scirra to investigate especially if its a large project, but, well, if I were in your position, that would feel like my only hope with such a severe issue.
Do you have other info you can think of - did you mess with containers a lot in your project? Did you only add containers recently? Have you had a look at your c3p file with 7zip/zip software, does it open? Is it blank? Is it corrupt when you try to open it and open a random file within? Does this happen with any other projects? If unsure, try making a new project or take an example project, save it, close, open.
I even wonder if "container" is a red herring in the context of Construct, maybe it's not container-related but a weird generic error message referring to another type of "container" within JS/html.