A corrective release of Firefox 91.0.1 is available, which includes several fixes:
- A vulnerability (CVE-2021-29991) has been fixed that allows for a partitioned HTTP header attack. The issue was caused by an improper acceptance of newline characters in HTTP/3 headers, which could allow a header to be interpreted as two different headers.
- An issue causing button resizing in the tab bar has been resolved, which occurred when loading certain websites that used Unicode codes for mathematical symbols in their headers.
- A problem that led to tabs from windows opened in private mode appearing in regular windows while browsing suggestions in the address bar has been fixed.
Additionally, it is worth noting that in Firefox 92, scheduled for September 7, WebRender is expected to be enabled by default for all users on Linux, Windows, macOS, and Android, without exceptions. In the subsequent release, Firefox 93, support for options to disable WebRender (gfx.webrender.force-legacy-layers and MOZ_WEBRENDER=0) will be discontinued, making this rendering engine mandatory. WebRender, written in Rust, significantly increases rendering speed and reduces CPU load by offloading page content rendering operations to the GPU, implemented through GPU shaders. For systems with older graphics cards or problematic graphics drivers, a software rasterization mode (gfx.webrender.software=true) will be used in WebRender.
Source: opennet.ru
