Workaround for the see-through gaps bug

js/term_screen.js

@@ -1146,6 +1146,8 @@ window.TermScreen = class TermScreen {
       this.screenAttrs = new Array(screenLength).fill(' ')
     }
 
+    let bgcount = new Array(256).fill(0)
+
     let strArray = !undef(Array.from) ? Array.from(str) : str.split('')
 
     const MASK_LINE_ATTR = 0xC8
@@ -1167,6 +1169,7 @@ window.TermScreen = class TermScreen {
         else this.blinkingCellCount--
       }
 
+      bgcount[bg]++
       this.screen[cell] = lastChar
       this.screenFG[cell] = fg
       this.screenBG[cell] = bg
@@ -1223,6 +1226,18 @@ window.TermScreen = class TermScreen {
 
     if (this.window.debug) console.log(`Blinky cells = ${this.blinkingCellCount}`)
 
+    // work-around for the grid gaps bug
+    // will mask the glitch if most of the screen uses the same background
+    let mostCommonBg = 0
+    let mcbIndex = 0
+    for (let i = 255; i >= 0; i--) {
+      if (bgcount[i] > mostCommonBg) {
+        mostCommonBg = bgcount[i]
+        mcbIndex = i
+      }
+    }
+    this.canvas.style.backgroundColor = this.getColor(mcbIndex)
+
     this.scheduleDraw('load', 16)
     this.emit('load')
   }