Dia 1.40.0 for macOS

Dia 1.40.0 focuses on browser performance and memory.

• Re-enable back/forward cache. Re-enables Chromium's back/forward cache for instant back and forward navigations, keeping recently visited pages alive in memory instead of reloading them.
• Free up memory from idle tabs. More of your unused tabs can now be put to sleep in the background, freeing up memory so Dia stays fast and responsive.