“Screen readers always "sit" on top of another application (for example a web browser or PDF viewer), conveying its contents to the user through audio (synthetic speech) or braille. As many of those applications do not care too much about accessibility and present their content in non-semantical or other inadequate ways, screen readers try to compensate for this. In addition, many websites are coded poorly, and some screen readers even try to compensate for this. While this works sometimes, in other situations it results in strange behaviours. Thus, screen readers often are perceived as being buggy. To prevent bugs, it is best to follow established standards and best practices.
“[…] Screen readers sadly seem to be very prone to regressions, meaning that a feature which worked well in an earlier combination of browser and screen reader versions does not work anymore in subsequent versions. For example, the fact that a specific accessibility feature worked well in the combination of NVDA 2021.1 and Firefox 89 is no guarantee that it will still work in NVDA 2021.2 with Firefox 91 (or NVDA 2021.1 and Firefox 91).“ Accessibility Developer Guide
knowing that things break easily, it’s important to report the issues you get. screenreaders and many browsers have support forums and/or email addresses you can tap in. cohost also has a support page for bugs and issues where you can describe what’s going wrong on your end.
if you are a developer, other developers wrote how to debug accessibility issues step by step.