You may get some stares at a street from time to time, there may be some people at work, talking from your back. Other than that, in Prague people do not care when gay couples kiss or holding hands together
Czech people may say that they are tolerant but it's not completely true. Czechia is the last EU member to adopt non-discriminational policies towards minorities and most of those laws are not working or activated when you need them. No prosecutor will want to deal with you or your problems.
If you have been the victim of some domestic violence or open workplace discrimination, there will be no protections for you at all and no prosecutions for the aggressor. The worker's rights are almost non-existent for ex-pats who work in foreign companies. The foreign investors are aware of this factor and it is a big advantage for them. That's why they continue to invest here.
If you are queer or gender non conforming, be ready to be rejected even from jobs that you are even overqualified. Also, it is not uncommon that when you want to rent a place which is available for foreigners, suddenly becomes "promised to someone else".
Majority of state officials, doctors or cops are not happy to deal with foreigners. Finding some assistance in English is non-existent. For example, when you involve in some traffic accident, the police may want you to sign some papers in Czech, to prove you guilty even you are not. And if you are an openly LGBT+ person, these negative behaviour will be multiplied by 5x. If you are beaten by some bodyguard, as a woman, there will be no prosecution. If you need any help towards any discrimination or violence by some authority you had due to your sexual orientation or gender identity, there will be no help from local LGBT organisations at all. The LGBT organisations mostly are about organizing the parade of Prague pride, or some other EU Funding projects. Nobody will help you when you need a job or shelter.
Also, there is some huge barrier against foreigners and locals, due to culture and language and when you are LGBT+, it is worse. You may want to blend with queer communities, but then you will definitely encounter the same barrier towards foreigners. Nobody will care to switch languages to include you to their discussions like some other western European countries.
Oh, by the way, how do I know these? Because as an openly queer woman I lived all of the negative examples, I was beaten by a male bodyguard in a pub for no reason, I was discriminated in the workplace and cancelled contract (lawyer said they would fire me without bonus, so I had to accept what they said), been subject to mobbing by coworkers, phsically attacked by father and sued him (I had the health report stating that I was beaten) but they said I had no proof, refused many job interviews after I went there, could not find a decent home for a long time, had a mental breakdown (shared some suicidal thoughts on social media) and police took me to hospital, I was conscious and calm, they said that I had to sleep in the psychiatric ward, I refused, even my brother stepped in, but the night shift doctor ordered police to tie my hands and forcefully injected sedatives (they apologized the next day), everything may seem fine until you raise your voice, try to fight for your rights or at least demand to be treated as a decent human. So be careful and know that this is not LGBT heaven.
After all of these years, my solution to these was, to keep a very low profile, not being openly queer and not sharing my gender identity or orientation with someone. Nowadays I have a better life, but in the end, I accepted things as they are.
Do not get me wrong, Czech people are awesome, 99% of them have golden hearts, better than anywhere else in Europe. It is sad to write these lines about the most beautiful city and country of Europe. But in these issues, we are not anywhere yet.