I'm sorry that you're having to deal with this concern. Can you please explain how this would help? You seem both concerned with comments that you write and those that are written by others. Even if SE implements a way to notify you when/if your comments are deleted, you still won't know that other people have had theirs deleted. Making the comments visible to everyone even after being deleted defeats the purpose of deleting them.

@DaMaxContent And that never causes any drama.

That seems like it could get really messy if it marked each specific comment removed... do you mean something simply like {this post has X deleted comments}? I have often deleted dozens of comments on posts, all at once... Mods can see such a message, I suppose that it could be something that could be made visible to everyone ... but are you sure that would help? Knowing that comments were deleted won't tell you what the comments were.

Have you considered talking to the mods on the sites you use to see if they would be willing to let you know whether comments had been removed if you were to ask?

@DaMaxContent So you're now saying that this shouldn't be a feature for everyone, but rather a feature for just you, specifically, and no one else? And you think that it's a reasonable accommodation for every single website you ever use to add in custom development to support just you so that you can know if any change to the site was something that actually changed or just something you thought had changed? That's...quite a significant accommodation. You also can't say that you've been prohibited from discussing it; you're discussing it now.

@DaMaxContent Your wording implied that the feature would only be available to you, and not to others, thus I asked if you were actually proposing that it only be available to you, or if that wasn't what you were actually suggesting. If that's not what you're suggesting, then fine, I misinterpreted that; that's why we clarify things. If you don't want people to be defensive, then I'd advise against threatening legal action, it's not a good way to get people to open up to you.

Just an FYI, if this is as a big deal as it seems to be, be aware that answers/questions can also be deleted without notification and so as a result SE might be by design not necessarily the most accommodating environment if a permanent record of 100% of your actions is important to you.

@DaMaxContent When you say to someone, "I wouldn't sue you if you don't do what I want, but someone might end up suing you if you don't do exactly what I want" then that's, frankly, threatening legal action. Ostensibly not by you, but still a threat of legal action nonetheless. Bolding and italicizing something like that only makes the implication all the more clear.

Since having a record of your comments -- which you agree are ephemeral -- is important to you, and you know this at the time you post them, can you address your issue by taking a screenshot (or saving the page)? Part of the idea of reasonable accommodations is that both parties do what they can; this is something you can do to mitigate. For example, as a visually-challenged person I know I have to sit up front at presentations even if I'd rather hang out in back, but if even that doesn't help I can reasonably request a copy of the slides to follow along in. Both parties do their parts.

I'm glad that you like my answer but accepting it doesn't mean that anything in it will be implemented... I think you should wait so that the discussion can continue. Accepted answers often cause users to skip a question because they think it's already "solved".

@DaMaxContent That seems like a good idea. :) Something that saves comments to a file as you submit them. :D

You could try the Stack Apps chat room chat.stackoverflow.com/rooms/111347/sobotics I think the people in there can help you do something like that... you could also try Stack Apps, though I don't know the site very well.

I strongly suspect that could be done with a userscript, though I don't have the necessary knowledge to write it myself. I've seen "annotate web pages" scripts/extensions floating around in the past (for web pages in general, not specific to SE). There's probably a way to hook into the "add comment" button click to scoop up the text and stash it somewhere.

While I agree this will help you, Stack Exchange is not, and should not, be responsible for people's health. If you feel using SE might harm your health I'm afraid the best course of action is to just not use it.