blindGram 8.0 Beta 5 tested Telegram 7.2.1 before the final
blindGram 8.0 Beta 5 went out on December 1, 2020, on Telegram 7.2.1, five days before 8.0 Final. The post itself carried no separate feature list.
This is an archived beta announcement. Telegram had recently added comments on channel posts and multiple pinned messages, and 8.0 was the blindGram release that made both work with a screen reader. This beta is where that work was tried on real phones before the final went out. The attachment's name pins down the Telegram base it was built on, and what it changed is written up in the final's own notes rather than here.
Five days later the release followed. Read what it brought in blindGram 8.0 made Telegram comments accessible. The earlier 7.0 beta round is at blindGram 7.0 Beta 7.
Betas are still posted in @blindGram_BETA2, and the current release is on the download page.