twilight venturesopen a large log file in the editor
A .log file is what a service leaves behind, one line per event, until it is longer than any text editor wants to load. Rotation splits it into a set, app.log for the newest lines and app.log.1, app.log.2 and up for the older ones, the oldest often gzipped to .log.gz. A line is plain text, a JSON object or logfmt pairs.
in a jetbrains ide
Install Log Lens from the JetBrains Marketplace; it runs in IntelliJ IDEA, PyCharm and every IntelliJ-based IDE from 2024.2 on. Log Lens opens .log, .out and .err files, rotated .log.N files and each .gz form; a .txt file stays with the text editor. Every file it opens gets a Log Lens tab beside the regular editor, which is never taken over. Lines are indexed by byte offset in the background, so the log opens at once, and a .log.gz is decompressed to a temporary file first.
in vs code
Install Log Lens for VS Code from Open VSX or the Visual Studio Marketplace; it runs on VS Code 1.90 or newer. The text editor stays the tab that opens first: Log Lens is the Open With choice on the file and the Open in Log Lens command, on the same names the plugin claims. Lines are indexed by byte offset in one pass, and a .log.gz is unpacked once to a temp file that goes when the tab closes.
what you see
The log is a table, and the format is read from the file itself, plain text, JSON lines or logfmt. When the level pass finishes, the chips over it carry whole-file counts of ERROR, WARN, INFO, DEBUG and TRACE, and one click narrows the view to a level. Find in file searches every line with a match count and a next and previous jump; the extension also takes a regular expression, with Matches only to page through the hits. A selected line goes whole into the line detail, and an ANSI line shows in its colors. The extension pretty-prints a JSON line there, and its Statistics tab gives the line count, the size and the level counts.
what the plugin has that the extension does not
Jump to source links a stack-trace line into your project. The Encoding selector in the toolbar sets a log's encoding by hand, and the view and search follow the pick; the extension has no selector, and the first 64 KB decide how it reads the file. Pro in the plugin also exports to Parquet, with the parsed fields as typed columns and the raw line beside them.
free, and what Pro adds
Reading is free, and neither side calls the network to read. Both paid tiers are subscriptions with a 30-day trial: the JetBrains plugin has a subscription of its own, while the VS Code extension shares one Lens Pro key with JSONL Lens and Parquet Lens for VS Code, and its trial runs per machine. Pro on both sides adds whole-file filter queries, export to .log, JSONL or CSV (Parquet as well from the plugin), log statistics (the time span and the activity histogram over the free counts) and grid themes.
What is free today stays free in every later build; we add to Pro and take nothing away.