Mozilla Firefox 156 Optimizes JPEG Image Handling to Cut Memory and CPU Usage
Mozilla has released Firefox 156 with optimizations for handling large JPEG images. The browser now uses less memory and processor time when websites display downsized versions of high-resolution photographs.
Normally a browser must fully decode a JPEG file before scaling it to the required dimensions. Firefox 156 reduces the cost of this common operation, which occurs frequently on photo galleries, e-commerce sites, and news feeds that may contain dozens of such images.
The company does not publish a single performance figure because savings depend on original file sizes, the number of images, and the user’s hardware configuration.
PDF Viewer Improvements
A second notable change improves the built-in PDF viewer. According to Mozilla, it can now start up to 45 percent faster. The difference is most noticeable on the first opening of a document, when the browser loads required components.
The update rolls out on 15 September for supported desktop platforms. Users can check for it via the menu path Settings → About Firefox, after which the browser will download the new version and prompt for a restart.
Related articles
Prod is Down: Free gVisor-Based Simulator Gives Strangers Root Access for Realistic Linux Incident Training
A Russian systems administrator has launched Prod is Down, a free online platform that lets users practice real incident response by granting them root consoles on deliberately broken Linux servers. The tool currently offers 13 scenarios covering PostgreSQL failures, OOM Killer events, full disks, expired certificates, nginx 502 errors, inode exhaustion, DNS issues, and open file limits. Each exercise runs inside gVisor sandboxes with strict resource limits, internal-only networking, and automated verification that checks service health rather than player commands. The author implemented an emulated systemd in Python so trainees can use familiar systemctl and journalctl commands without running a real init system. Multiple layers of isolation, including overlay filesystem tweaks and size monitoring, prevent abuse while still allowing sudo and realistic debugging. The platform records three random variants per scenario so memorized fixes from previous runs do not work on subsequent attempts.
Home Lab Guide: Deploying Active Directory, Windows 7 Client and ELK Stack for Security Logging
A detailed tutorial walks readers through building an isolated VirtualBox lab featuring a Windows Server 2019 domain controller with DNS and DHCP, a Windows 7 client joined to the domain, and an ELK stack running Elasticsearch, Logstash and Kibana 9.4.2. The guide covers creation of organizational units, Group Policy Objects for advanced auditing, and configuration of Winlogbeat 7.17 to forward Security, System and Application logs to Logstash. Special attention is given to common pitfalls such as missing GPO extension attributes that prevent audit policies from applying and memory constraints when running the full ELK stack on limited RAM. The author emphasizes that Windows 7 is unsupported and should only be used in isolated lab networks. All steps are provided with exact PowerShell commands, netplan configurations, and Logstash pipeline examples suitable for a 192.168.100.0/24 NAT network.
Building Your First Home Network Lab: Essential Tools and Experiments to Understand Corporate Networks
A cybersecurity professional without network knowledge resembles a guard without a building blueprint, spotting alarms but unable to trace the intruder. Setting up a personal lab on a standard computer bridges this gap through virtualization and hands-on practice with protocols and attacks. The guide recommends GNS3 for topology emulation, VirtualBox or VMware for running Windows and Linux workstations, Cisco Packet Tracer for quick simulations, Wireshark for traffic analysis, and draw.io for diagramming. Key experiments include configuring Cisco IOS routers with IP addressing, testing default gateways, observing ARP requests and replies, triggering broadcast storms via switch loops, and enabling STP to prevent loops. The lab demonstrates how legacy protocols like ARP expose networks to spoofing and why segmentation with VLANs and firewalls matters. Resources from CyberED provide demo access to courses on SOC analysis, penetration testing, and AI applications in security to extend learning.
PSLC and Agent-Ops: From Product Support to Infrastructure Transformation
Sergey Zhitinsky, founder of Git in Sky, attended the OPS Talk by Sber meetup on October 19 and discussed the PSLC methodology with architect Alexander Shapovalov. PSLC, or Product Service Lifecycle, outlines two loops for restoring services immediately and improving reliability to prevent recurrence through teams, knowledge, and platform support. Agent-Ops focuses on eight detailed steps for individual infrastructure tasks: intention, evidence collection, diagnostics, planning, approval, controlled change, verification, and lessons learned. The article illustrates their complementary use in a scenario where post-release log growth fills a database disk, requiring both service restoration and root-cause fixes. Both approaches emphasize knowledge retention, action control, and human accountability, though Agent-Ops v0.5.1 mandates explicit human approval and separate execution for production changes. PSLC suits larger organizations with shared platforms, while Agent-Ops targets smaller teams handling infrastructure operations with AI agents.