According to the official documentation (https://support.smartbear.com/testcomplete/docs/app-testing/web/supported-browsers/index.html), TestComplete does not yet support Firefox ESR 140. You’re free to try it out, but you may encounter issues that won’t be officially addressed until compatibility is added.
Based on SmartBear’s past cadence—typically delivering new ESR support within 4–12 weeks of the ESR release (Firefox ESR 140 went live June 24, 2025)—I’d estimate official support arriving around October 2025.
To help accelerate this, please open a support ticket with SmartBear and stress your urgency. High-demand versions often move up the roadmap.
Note: This reply was drafted with AI assistance and references only official SmartBear TestComplete documentation.
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