Release Status

The last stable release of NVDA was 0.5, released in May 2007. Since then, there have been a huge number of changes to NVDA, many drastically improving the user experience. One of the biggest changes is the introduction of the new, in-process virtual buffer code for Mozilla Gecko 1.9, which will make rendering of documents almost instantaneous and greatly improve accuracy in applications such as Mozilla Firefox 3.0. Many people are using development snapshots instead of 0.5 because of the fact that NVDA 0.5 is so outdated. This is not an ideal situation, as most casual users would prefer to be using a release declared as stable. As a result, a frequent question is when another stable release of NVDA will be made.

Unfortunately, there have been several regressions since 0.5 which cannot be fixed in the near future. (A regression is some functionality which worked in a previous release, but which subsequently does not work correctly in a future release.) Perhaps the largest regression is in the support for Microsoft Internet Explorer documents, which, aside from Microsoft Internet Explorer itself, are used in many other applications where HTML documents are displayed, such as Microsoft Outlook Express and Microsoft HTML Help. The old core virtual buffer code used by the Internet Explorer support implementation is slow, buggy and otherwise inferior to the new, rewritten core virtual buffer code. Thus, rather than focusing our efforts on maintaining code which is going to be replaced, we have almost completely abandoned it. As a result, support for Internet Explorer documents is now more broken and buggy than it was in 0.5. (This also applies to Mozilla Gecko 1.8, used by Mozilla Firefox and Thunderbird 2.0. However, Mozilla Firefox 3.0 is near release, so this will not be a great concern for much longer.) Currently, we are focusing on the new implementation for Mozilla Gecko 1.9, as mentioned above. We do plan to implement support for Internet Explorer documents using the new core virtual buffer code, but this is not likely to happen for several months.

We are not willing to make another stable release of NVDA with such major regressions from the last stable release. There are also several other major issues which need to be fixed before we can declare some of the new code stable. Unfortunately, this means it will be several months before we can even consider making a stable release. However, we recognise that using development snapshots is not ideal for some, as, although this rarely occurs, there can potentially be snapshots where large areas of functionality are broken. Also, we would like to have a release which can be demonstrated and easily obtained by those at the CSUN conference.

We have therefore decided to make 0.6 preview releases. Preview releases may contain regressions and there may be some major issues which must be fixed prior to the next stable release. However, we will endeavour to make them as stable as possible. They thus provide a preview of the upcoming stable release and allow users to run newer code without the uncertainty associated with development snapshots. Put in other words, they lie somewhere between development snapshots and stable releases in terms of stability and certainty.