Do Covid vaccines create specific antibodies which dominate the body's natural non-specific antibodies in a way that could cause future harm?

Yes, the COVID-19 stimulates your immune system to rpoduce, inter alia, antibodies. All antigens (anything that stimulates the immune system) do this.

Your body is always making new anti-bodies to substances the immune system has never seen before.  Ever get a splinter from a piece of pine wood?  You now have anti-bodies to some little protein in pine would.

Antibodies ARE specific.  That is why you need a different flu shot every year.  The flu shot is for the three strains of flu that are most likely to spread that year.  There are three vaccines in the shot, each one matches a specific strain. 

nope..............................................................

I'm afraid you're the one who's confused.  There's no such thing as a "non-specific antibody."  Each antibody is specific for a particular antigen.  At any given moment you have antibodies circulating against any number of pathogens--both those developed against viruses you've been previously exposed to, as well as against viruses for which you have been previously vaccinated. But as long as there is no ongoing invasion by one of those pathogens, then the amount of any one type of circulating antibody is not very high.

If you are infected with a pathogen for which you have antibody "memory," then yes, the immune response will crank up and specific B cells which produce the appropriate antibody will preferentially proliferate, and for a time, the specific antibody they produce will predominate in your system, and outnumber all other antibodies that are specific for different pathogens. But as the infection is brought under control and the pathogen is dealt with, then the response ramps down, because most of the active plasma cells (the B cells that are secreting antibodies specific for that particular pathogen) die off--all that's left are the memory B & T cells which stick around in case there's yet another exposure to that same pathogen.

That's the way your body makes antibodies, whether it's in response to an actual infection or to a vaccine.  In very rare cases, ANY vaccine may result in an autoimmune dysregulation, for reasons that nobody really understands very well, but that is possible with ANY vaccine, not just the ones for C-virus, and again, it's extremely rare.

With these mRNA vaccines, the only real dfference is that it's our own cells that are producing and releasing antigen (the so-called spike protein) encoded in the injected mRNA, instead of directly injecting that antigen. But that mRNA does NOT stick around for long. RNA  in general is highly labile and is degraded quickly in the cell. That's part of its normal job--our own mRNA is just a disposable, working copy of a gene, that only sticks around long enough to have some protein translated off of it, then it's rapidly destroyed.  Same with these mRNA vaccines--cells pump out spike protein, then that mRNA gets chewed up.  Meanwhile the spike protein floats around and antibodies are generated in reponse to it.  And as long as those antibodies were generated in a T cell-dependent manner, then a long-term cache of "memory" B cells will exist, ready to crank things up if the vaccinated person is exposed to the C-virus.

But like any other memory B cells, these remain quiescent unless the specific pathogen against which they were generated makes an appearance.  If you've been vaccinated against SARS CoV-2, but you never get exposed to it, then you will still have memory cells that lie in wait. They may never get called upon, in which case you'll have a small "club" of COVID-19 memory cells that just sit around doing nothing for the rest of your life.  Or some infected person coughs in your face, in which case you're off to the races.

"dominate the body's natural non-specific antibodies"?

What does that even mean?

What makes you think there are non-specific antibodies?

No, that's complete nonsense. At any given moment, the average adult is making thousands to millions of different antibodies against different things. Adding one more is not an issue.

First of all, every antibody molecule in your body was produced against some foreign substance, molecule or organism that your body encountered at some point. There are no "non-specific" antibodies in your blood stream. 

No antibodies produced against one virus are ever really effective against a totally different virus. So, there is no reason to imagine that the antibodies produced against the current virus or from the vaccines would neutralize any virus that isn't closely related to the current virus and its variants. So saying that the vaccine won't protect you against other viruses is just a dumb statement--of course it won't.The current Covid vaccines cause your body to make many different antibodies (a polyclonal response) to the spike protein of Covid. Any closely related variant should have spike proteins that are sufficiently similar that the antibodies produced should be at least partially effective. The current evidence is that the vaccines are pretty effective against the variants that have been seen so far.

Might a new variant appear with a spike protein that is so very different that the current antibody responses don't recognize it at all? Sure, its possible, but pretty unlikely, particularly if large numbers of people get vaccinated quickly.

Every time you get vaccinated you get new antibodies.  You got them for polio, whooping cough, chickenpox, every flu variant yearly,  etc.

No, doesn’t work like that and specific antibodies to anything to do this.